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  • La physique de la modélisation du climat « RealClimate
    a perfect system i e using a model to predict what another run of the same model produced you can show that there is useful information in ocean initial conditions for about a decade mostly based on the North Atlantic However in the presence of strong forcing rising greenhouse gases volcanoes etc the predictions become much less dependent on the start So for the 20th century trends where we have essentially no information about the ocean initial conditions it is easy to see that the global trends even over decadal to multi decadal time scales are robust to the starting fields Skill in prediciting regional changes however even in a perfect set up is not very high mainly because of the amount of unforced weather noise which neither kind of prediction can capture gavin 11 CobblyWorlds says 6 Jan 2007 at 4 08 AM Re 8 No Alastair The CC net information page was as implied an addition for other interested amateur readers I ve not run any climate models merely read papers Were I to run a climate model I don t know I d have the skills to be sure whether it had correctly produced such a thing as the ITCZ 12 Barton Paul Levenson says 6 Jan 2007 at 12 44 PM Re The idea that mankind s small percentage of the carbon cycle could be the cause of the Mauna Loa graph seems to this layman to be unlikely the attribution owing more to man s overwheening vanity than scientific measurement like claiming the Earth as the centre of all things From 1750 or so to 2005 the ambient CO2 concentration rose from about 280 parts per million by volume to 380 ppmv We know it s from fossil fuel burning because we can measure the fraction of C14 and that has been declining There s virtually no CO2 left in old fossil fuels simply because their age is many times greater than the C14 half life This is the smoking gun that shows the CO2 is anthropogenic and not from some natural process All the CO2 in the biosphere has roughly the same mean level of C14 13 James says 6 Jan 2007 at 2 21 PM Also the amounts of fossil fuels used in the last century are quite well known you can look up the numbers in various economic statistical sources and from that you can easily compute how much CO2 was produced Add that up compare it to the observed increase and you ll find the numbers match Actually the amount of CO2 from fossil fuels is somewhat greater than the observed atmospheric increase because some gets dissolved in the ocean and so on Thinking of fossil fuel CO2 as man s small percentage is the wrong way to look at the problem The key word there is cycle all the rest with small exceptions like volcanic sources and geological sequestration is in a cycle that keeps going around and around The fossil fuel CO2 is an addition That addition may be comparatively small in any one year but it doesn t go away it keeps adding up 14 David Price says 6 Jan 2007 at 3 13 PM One question Have models taken in to account the increace in the number of thunderstorms that will result from warming I read once that thunderstorms keep the earth several degrees cooler than it would otherwise be As more storms happen the hotter it gets will they have a moderating impact Response Equilibrium requires a balance between downward and upward transport of energy within the atmosphere Thunderstorms should be thought of as simply one of many modes of behavior by which the atmosphere attempts to achieve this balance in this case largely through the vertical transport of latent heat associated with condensation of water vapor within storm clouds Obviously individual thunderstorms cannot be represented at the coarse spatial scales resolved by GCMs However their principal role in terms of energy balance as described above is represented in models through the parameterization of convective instability in the atmosphere Mike 15 mzed says 6 Jan 2007 at 11 09 PM 12 think you meant There s virtually no C14 left in old fossil fuels 16 Barton Paul Levenson says 7 Jan 2007 at 8 02 AM Re 12 think you meant There s virtually no C14 left in old fossil fuels Yep you ve got it My bad 17 Julian Flood says 7 Jan 2007 at 12 00 PM Re 5 Thank you for your reference I ve not replied to thank you until now because I ve been thinking Your reference is dated 1996 and as such the author had no access to the work was it by Morel et al I ve looked at so many abstracts today my gyros are toppled about C4 and beta carboxylation pathways in phytoplankton Under stress some phytos change from C3 metabolism and the isotopic fractions they sequester change the heavier molecules are not discriminated against so strongly So my ocean pollution hypothesis is up to this objection reduced upwelling and lessened entrainment of the surface by wind results in depleted zinc and cadmium levels Stressed the plankton switches to C4 beta carb and begins to rain out C13 enriched detritus depleting relatively the upper ocean of C13 in an isotopic refinment of the biological pump The ratio of C12 rises The normal process of mixing ensures that the air and water concentrations of the new isotopic balanced CO2 mix and match The atmosphere exhibits depleted C12 Surface pollution is worse in the Northern hemisphere and continued healthy upwelling in the Southern hemisphere helped by being less complicated by contraints of narrow seas means that the phytos there are less stressed and can continue their usual C3 way of life How then should an oceanic CO2 source cause a simultaneous drop of 13C in both the atmosphere and ocean Not a source A relative sink for C13 ref 13 the numbers match Have I got this wrong I ve seen references that half of the anthropogenic carbon is sequestered Half is not what I call a very good match However I d be grateful for references which tie this down a little more strongly as I m sure the science does not depend on a simple post hoc argument and I d like reassurance ref 12 The smoking gun indeed If a plant switches to C4 metabolism a technique which apparently is less discriminatory between C12 and C13 would it also sequester unexpected amounts of C14 Presumably the differences are purely mechanical which would indicate this was so Does anyone know If C14 is being used up unexpectedly what does this do to the smoking gun Maybe I need to think some more There should be some testable predictions from this C14 levels in deep sediments should show increases from around 1850 as the stressed oceans began to react to the outward spewing of the nascent petrochemical industry Plankton samples if dead maybe frozen should show a lack of zinc and cadmium indicating that they have changed to different metabolic systems Is the data already out there I leave other tests to the intelligent reader JF 18 Hank Roberts says 7 Jan 2007 at 1 09 PM I ve been wondering where to look for the surprises One example much belabored is methane hydrates I see that only a few years ago geologists were still debating the origin of pingos not the Linux penguin This is fossil carbon too presumably depleted of C14 Is there any clear idea how and when the stuff is formed I can imagine it could be either a cyclical process associated with glaciation lower temperature at a given depth below sea level or contrariwise when the planet is warmer CO2 higher and sea level much higher because pressure is greater at that same location I wonder if the models state an assumption about this stuff either it s been locked down by past extremes so is stable or it s at an equilibrium state so released as warming proceeds in local spikes as brief temperature extremes occur in the location I d think that some would have bubbled out over the last geologically brief warmth at end of last ice age but that would have been almost done happening as the planet slowly cooled back toward the next ice age The big old ones look like hills tree covered I wonder if the Navy has mapped the polar sea floor well enough to count undersea pingos presumably secret if so as detailed maps but if so perhaps summary data on size and location would be interesting to try to quantify what s been happening As of 2003 the origin of pingo structures was apparently still being debated lots of good pictures for example here http www mbari org news news releases 2003 paull pingos html Now it appears clear as they re being observed below sea level that they do form as methane boils off Is there enough info developing to include this in models 19 Jason Goodell says 7 Jan 2007 at 2 45 PM After reading this months quick study on climate modeling in Physics Today I ve been unable to push this topic from my mind especially with it being nearly 70 F here in New England yesterday As a physicist with only a casual understanding of the issues surrounding global climate change I m drawn to the simple idea that humanities demand for energy is the central issue As the global population inceases and the spread of technology increases the demand for energy generation will also increase For our great grandchildren other factors like thermal polution and the effects of large scale solar and wind farms may be the climate issue of their era CO2 emissions are only the beginning of what will be a constant need for the consideration of our actions and their impact on Earth s climate 20 Julian Flood says 8 Jan 2007 at 4 52 AM Sorry typo in 17 in spite of lots of thinking It should read of course the atmosphere exhibits depleted C13 not C12 Sorry about that It has me wondering about the mismatch of CO2 rising after temperature in the historical records do the dating techniques depend on C14 levels and would C4 reduction of C14 pull the dates back into line JF 21 Alastair McDonald says 8 Jan 2007 at 10 03 AM Re 20 etc Julian Gavin s reference was to a FAQ produces by Jan Schloerer of Ulm University and hosted on the web by Dr Robert Grumbine of NOAA http www radix net bobg Although the article is now over ten years old it directly answers your question one that has been asked by global warming skeptics for all those years Jan wrote From its preindustrial level of about 280 ppmv parts per million by volume around the year 1800 atmospheric carbon dioxide rose to 315 ppmv in 1958 and to about 358 ppmv in 1994 If you go to the Mauna Loa site you can see that it has continued to rise since then to about 375 ppmv in 2004 http cdiac ornl gov trends co2 graphics mlo145e thrudc04 pdf There is no doubt that the increase is due to fossil fuel burning You only have to think about about 100 million Americans taking their cars onto the road and burning on average one gallon of fuel each day That is 500 000 000 tons of CO2 they are producing per day Globally we have put a trillion tons Pt of CO2 into the atmosphere See http cdiac ornl gov trends emis tre glob htm 305 Gt of C equals 305 44 12 1 122 Pt Well that s what 6 5 billion little unassuming people can do if you give them enough time 22 Hank Roberts says 8 Jan 2007 at 11 46 AM C12 C13 C14 All three contribute The 14C 12C and 13C 12C ratios SCIENCE VOL 279 20 FEBRUARY 1998 1187 Atmospheric Radiocarbon Calibration to 45 000 yr B P Late Glacial Fluctuations and Cosmogenic Isotope Production 23 Charles Muller says 8 Jan 2007 at 11 51 AM About parametrization In your text Gavin you explain equation approximated physics eg radiative transfer and empirically based physics eg evaporation need for parametrization That s not really clear for a non expert do you mean for example that different coefficients of equations for these phenomena are to be regularly corrected from real world measurements and retrovalidation About emergence You say on one hand that large scale behaviors of climate are robust but on the other hand that they emerge from small scale and more chaotic features Does it mean that chaotic small scale behaviors of climate are after all without real concern for the accuracy of 2100 projection 24 Julian Flood says 8 Jan 2007 at 12 01 PM Re 21 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr I wonder why we assume that the C accumulating in the atmosphere is actually our C Why is there this tiny fraction of the overall flux which is not consumed The smoking gun did indicate that it s ex fossil fuel carbon because it is depleted in C14 as one would expect If C4 metabolism is disturbing the expected C14 levels then the bets are off The deep sea reservoir of C is 380 000 Gt Thinking non anthropocentrically why does our little flow go straight into the atmosphere Does it Obviously not because some of it gets lost Our flow is dwarfed by natural processes and we need to find a way of pointing at our emissions and proving that the trouble is what we re up to Otherwise we re like a little boy peeing into a lake and taking the blame when the dam bursts There s a sawtooth daily pattern to the Mauna Loa graph Is there any difference in the gas make up between day and night Does the isotopic makeup vary JF 25 Bryan Sralla says 8 Jan 2007 at 12 07 PM Re 10 Gavin thank you for responding Since a climate prediction problem of the first kind controlled by initial values will effect numerous non linear feedbacks which ultimately will effect the degree of free variations in the climate trajectories it seems well founded to me that many classes of climate prediction problems are controlled by intial values Do you agree with my statement Also greater numbers of non linear type feedbacks added to the AOGCMs will most likely increase the degrees of free variations in modeling experiments Right It then seems feasible that improving the models making them better resemble the real thing may make skillful multi decadal predictions more contolled by initial values not less since the amount of noise in the system is greater relative to the forced variations Since a boundary values problem is superimposed over the initial values problem in real climate prediction it seems necessary to obtain solutions which satisfy both types of equations for many climate prediction problems I think for some casual observers it might seem non intuitive that improving the models adds to more uncertainty in predictions The more I read and study the problem the more I am pursuaded you modelers have a tough problem on your hands Good luck 26 yartrebo says 8 Jan 2007 at 12 49 PM Re 24 Those single celled organisms are releasing carbon that was only recently fixed Even in the short term 1 year period it is within 1 of being in equilibrium with carbon fixed by life The C4 pathway is only used by grasses Other plants and all bacteria and protozoa use the older C3 pathway An organism cannot just choose which pathway is wants to use Even if land use patterns have changed the ratio of C4 to C3 plants probably increased it because so much crop and livestock land is planted with grasses the effect will be quite minor as the carbon is released back into the atmosphere in short order As far as the deep sea reservoir of C goes don t forget that it takes thousands of years for the deep ocean to turn over and that while it is a reservoir it was more or less in equilibrium at 285 ppm CO2 and thus that carbon wasn t going anywhere With current CO2 levels the deep ocean is actually a net sink of CO2 absorbing a fairly significant share of our emissions With regards to the sawtooth daily pattern at Mauna Loa it s due to photosynthesis during the day and respiration during the night While there s probably a difference in the isotopic makeup it s probably pretty small Thinking non anthropocentrically why does our little flow go straight into the atmosphere Does it Obviously not because some of it gets lost Quite easy just look at a smokestack or exhaust pipe The CO2 literally goes straight into the atmosphere As far as what gets lost that s mostly the ocean absorbing about half of it It isn t gone for good and if CO2 levels drop the process will reverse releasing the CO2 back to the atmosphere 27 James says 8 Jan 2007 at 1 28 PM Re 24 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr Rather misleading language they don t push out that much CO2 except in the sense that you push out a certain amount of CO2 every time you exhale A better way to put it would be to say that they cycle through that much carbon it comes in it goes out but only if there is a change in the mass of soil organisms and their corpses etc does all that activity produce a net change in CO2 This does bring up a question I ve sometimes wondered about but have never seen numbers on suppose we could ignore the political obstacles and make a serious attempt at re vegetating areas the western US North Africa the Mideast Australia that have been desertified by human activity How much CO2 could we expect that to sequester 28 Hank Roberts says 8 Jan 2007 at 1 52 PM Julian here are papers addressing the questions you posed above just a couple from a large and interesting site You d want to check the citation index forward because these are relatively old papers not the current best info but a place to start There has been a lot of research addressing the questions you mention above and I am sure isn t news to the climate scientists It s an example of the details they have to consider http www igac noaa gov newsletter 16 co2 php Isotopomers of CO2 and their use in understanding the global carbon cycle One of the most striking results that 13C data and now O2 N2 ratio data unveiled is the existence of a very large repository of anthropogenic CO2 in Northern Hemisphere ecosystems during the early 1990 s when the atmospheric CO2 growth rate had diminished to only one third of its normal value Still the long term trend and interannual fluctuations of 13C at one given monitoring station is at the limit of detection of mass spectrometers on the order of 0 01 per mil for 13C in CO2 Thus even a very slight bias in the isotopic data would translate into different inferred magnitudes of the global land and ocean uptake of anthropogenic CO2 http www igac noaa gov newsletter 16 mass new php Biogenic aerosol formation in the boreal forest BIOFOR Anomalous or Not Strictly Mass Dependent Isotope Variations Observed in Important Atmospheric Trace Gases Variations in stable isotope ratios in the environment have generally been well understood and put to good use However the atmosphere appears to be the scene for a host of isotope effects that we do not yet understand The prime example is ozone whose anomalous enrichment has repeatedly defied correct interpretation Atmospheric studies also benefit from stable isotope variations An illustration is the ongoing decline of the 13C 12C ratio of atmospheric carbon dioxide largely in consequence of the increasing fraction of fossil fuel derived carbon dioxide This isotope effect is thus directly related to the isotopic composition of an important source of the gas Fossil fuels have about 2 less 13C than atmospheric carbon dioxide This in itself is obviously not a source effect ambient CO2 is the carbon source for plants but rather an isotope fractionation effect of photosynthesis Plants favor 12CO2 slightly over 13CO2 so the assimilated carbon is depleted in 13C relative to the atmosphere In isotope applications of interest to atmospheric chemistry source signatures and fractionation effects in chemical reactions are both relevant It has taken years to unravel the secrets of the anomalous isotope fractionation of ozone perhaps the most extensively studied reactive atmospheric trace gas In regard to molecular symmetry 17O and 18O in an ozone molecule are identical they are simply different from the abundant 16O isotope However theories based on symmetry have been challenged by the latest experimental data After ozone it was found that carbon dioxide in the stratosphere exhibits MIF Thiemens et al 1995 Gamo et al 1989 A chemical mechanism was proposed by Yung et al 1991 who showed that the observed 17O excess in CO2 could be explained by transfer of the enrichment present in ozone to CO2 via the excited oxygen radical 29 Hank Roberts says 8 Jan 2007 at 2 18 PM Another good source on where CO2 is coming from here dated early 2005 http www publish csiro au act view file file id EN05013 pdf Recent Record Growth inAtmospheric CO Levels Regrettably the actual data illuminating this question was collected at stations funded by the USA and Australia that are now being shut down the authors point out 30 Sally says 8 Jan 2007 at 4 01 PM Re 24 There s a sawtooth daily pattern to the Mauna Loa graph Is there any difference in the gas make up between day and night Does the isotopic makeup vary Is there a daily sawtooth pattern to the Mauna Loa graph There is certainly an annual sawtooth pattern caused by the northern hemisphere forests kicking in with photosynthesis every spring That is probably rather simplistic but I think it is what Charles Keeling set out to measure initially The carbon flux is affected by all photosynthesis terrestrial and aquatic There would be a daily flux however as plants respire all the time but only photosynthesize during light conditions Again this is a simple explanation and does not take into account the processes that go on in the dark to produce sugars If you go here http cdiac ornl gov trends co2 nocm htm you can look at graphs from the four collection stations at Barrow Alaska Samoa the south pole and Mauna Loa You will see from the graph found here http cdiac ornl gov trends co2 nocm sagr htm that there is far less fluctuation in Samoa as the climate has little seasonal change at this location I hope this helps 31 Donald G says 10 Jan 2007 at 5 26 PM I propose we invest massive resources into making a large array of petaflop scale computers dedicated to the study of global warming This way if the simulations show that Global Warming isn t an upcoming threat we ve ensured that it really is by churning out more than enough CO2 while making those computers 32 John Dodds says 10 Jan 2007 at 7 10 PM Re 24 30 Go to http meteo lcd lu today 01 html to see real live CO2 concentrations et al in Luxemburg Variations over 50 and as high as 500 ppm I agree that the patterns are complex Just changing the water vapor content rainstorms plays havoc with the CO2 concentrations as does the daily commute vehicle exhaust near the measuring station In general it is my understanding that the daily fluctuaions even the yearly cycle have a relatively small impact on the global warming consequences I think there is a Gavin comment to this effect from a year or so ago somewhere in the archives 33 Alastair McDonald says 10 Jan 2007 at 7 20 PM Re 24 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr Yes and they are better at sequestering carbon than us too They absorb 60 GtC yr too That is the oscillation you though were daily but are actually yearly We are what is making the curve rise 34 English says 12 Jan 2007 at 5 11 PM The text has both punctuation errors and errors of grammar Some of these errors are not insognificant The text of the document can be seen as ambiguous I would most respectfuly suggest that any text be checked for errors in grammar and punctuation by a technical author prior to publication Response Bit late now but what specifically did you find ambiguous gavin 35 Julian Flood says 13 Jan 2007 at 8 29 AM re 28 thanks for the sites even more thinking needed I read a recent CO2 metabolism paper for a particular species of phytoplankton and began to wonder about the chance that they are less consistent than science currently understands If the knowledge that certain marine plants can swap between C3 and C4 is only about 5 years old I d rather like to see whether their different fixation routes do odd things to oxygen isotope ratios There is a rather disturbing illo of the degree of confidence in the science of global warming low low and very low occur too often to be reassuring Governments make a lot of noise about global warming how odd that they don t throw large amounts of money to the only people who can demonstrate by scientific measurement exactly what s happening And yet monitoring sites are being abandoned why is that Do governments know something or is it merely complacency 30 thank you There s a daily wiggle rather than an annual sawtooth I believe but you re right I was conflating the two I m wondering if a signal of isotopic fractionisation could be teased out of the daily signal pinning it down to either worldwide or near ocean effects If the ocean surface pollution hypothesis of global warming is correct then this is the sequence the petrochemical industry kicks into life around 1850 Surfactant run off and oil spill begin to reduce stratocumulus cover the whole surface of the ocean warms reducing nutrient upflows and encouraging the phytoplankton to kick into C4 metabolism C4 phytoplankton increase in numbers as their relative advantage inproves over C3 plants C4 plankton sequesters more C13 than expected by conventional models expected levels of C13 fall producing a false anthropogenic signal Surfactant and oil pollution effects increase CO2 levels by reducing biological pull down mechanical mixing and reduce solubility by warming the surface What happens to the albedo of a polluted surface I don t know Deep water warms slightly Methanophages begin to emit more light isotope CO2 as the clathrate deposits become more accessible CO2 warming increases The ocean surface becomes even more stable and the cycle continues Eventually the clathrates boil off Result large temperature spike and collapse of civilisation I wonder if there s anything in the fossil record which would fit this scenario triggered perhaps by the breaching of a large light oil reservoir by coastal erosion I wonder what signals a scenario like that would leave for us to interpret Well I like it better than a convenient volcano boiling off a carbon deposit JF 36 Peter Erwin says 15 Jan 2007 at 4 30 AM Re 27 This does bring up a question I ve sometimes wondered about but have never seen numbers on suppose we could ignore the political obstacles and make a serious attempt at re vegetating areas the western US North Africa the Mideast Australia that have been desertified by human activity Most of those areas have not been desertified by human activity they re naturally deserts part of the global desert belts at low latitudes Vegetating them on a large scale would probably require significant energy expenditures and accompanying CO2 release for fertilization water transport and building the necessary infrastructure This is not to say that it s a bad idea to reverse desertification in local areas where it s recently occured of course 37 Alastair McDonald says 15 Jan 2007 at 9 16 AM Re 35 Julian there is a major event in the fossil record called the PETM Paleocene Eocene Thermal Maximum See http www es ucsc edu silab biocomplex lptm background htm 38 John Dodds says 16 Jan 2007 at 7 58 AM From the various Hansen et al and other papers the computer calculations of global warming show that adding CO2 results in the added CO2 molecules delaying not trapping the transport of energy out of the earth system and the subsequent global warming of the air near the ground and cooling near the top of the atmosphere TOA see cartoon figure 2e from Hansen et al 2005 This is the Greenhouse Effect The global warming effects results in a positive energy imbalance or disequilibrium at the TOA where more solar energy is coming in than is being sent out because the TOA temperature is colder than the equilibrium This apparently lasts for years if not forever per the GCMs Hansen Nazarenko et al 2005 However on a daily basis the Earth goes through a daily rotating solar cycle where at night we have a negative imbalance with more energy out than in then as the sun rises we warm up pass through the equilibrium point to get a positive imbalance and stay that way until the sun again starts to set and the energy in again passes through the equilibrium point and we return to a negative imbalance The same process happens when we get yearly seasonal temperature cycles and also on the approximately 11 year solar energy cycles which change the energy in amounts At all times the amount of energy being transported out of the Earth system is calculated by the Stefan Boltzmann Law SBL based ONLY on the temperature of the Earth system be it at the ground or at the TOA The SBL which says that the energy transported from an object is proportional to the temperature raised to the 4th power ie hotter air rises faster convection or hotter objects radiate more energy per unit time radiation transport is forever trying to reestablish the earth to its equilibrium energy in equals energy out conditions by either warming or cooling it and it is perfectly successful exactly twice each and every day This contradicts the conclusions of the Global Computer Models GCMs which require a permanent or multi decade disequilibrium or energy imbalance to create the global warming So the question is WHY doesn t the Stefan Boltzman Law feedback also automatically compensate for the greenhouse effect Why doesn t the feedback from the SBL automatically return the air to its equilibrium to solar energy in conditions imposed by the daily solar cycles Why isn t the delay in energy transport by adding GHGs compensated for by the speedup in radiation transport at the speed of light caused by the increase in temperature and the SBL response The SBL has no way of differentiating between a GHG or solar caused warming According to the GCMs we already know that the CO2 caused global warming results in hotter air rising faster convection at ground level which Gavin says is included in the GCMs as a part of the water vapor feedback effect How not to attribute climate change comment 182 12 57 pm see also 126 et seq 208 Why doesn t the hotter air at ground level also cause more energy to be radiated out faster per the SBL to result in the greenhouse caused warming energy to be returned to the TOA where the extra energy will cancel out the CO2 caused imbalance at the TOA ie to return the Earth to its equilibrium conditions which it actually does twice a day The conventional wisdom that greenhouse gases cause global warming is based on the identification of the greenhouse effect GHE in the Svante Arrhenius 1896 paper see Wikipedia On the Influence of Carbonic Acid in the Air Upon the Temperature of the Ground However my simple reading of the paper shows that Arrhenius calculated the warming effect of CO2 energy absorption in academic isolation CO2 absorbs energy without considering the real world effects of the Stefan Boltzmann Law Feedback Also a review of the Global Computer Models GCMs results shows that the amount of global warming calculated varies depending upon the duration of the period modeled eg 1950 1997 1880 2000 1750 2000 or from the bottom of the ice age and bottom of the CO2 level 20 000 years ago until 2000 etc This is to be expected except that the computer model also requires that the temperature imbalance at the TOA be equal to and opposite the warming to maintain conservation of energy SO just what is the temperature at the TOA in the year 2000 It HAS to be a single value not the infinite number of options that can result from the GCMs Again the GCMs are calculating results that are not possible BUT if the SBL Feedback returns the TOA to the equilibrium conditions then we have a single value but then there is no energy imbalance However there also is no global warming due to the GHE Sorry Gavin but I feel that the GCMs are giving such fundamentally incorrect inconsistent results that they can NOT be valid They seem to be missing some of the SBL feedback If you can explain these discrepancies please do Which brings us back to what you previously stated 15 months ago Response You refuse to relax your incorrect assumption that the flux from the surface is the same as the flux from the top of the atmosphere which is equivalent to assuming that there is no GHE at all So you assume the result you wish to prove gavin Comment by John Dodds 30 Oct 2005 8 04 pm click on the time stamp to go to Gavin Schmidt s RealClimate org location To which I now respond Yes Gavin I intuitively assumed constant equilibrium flux but it is not my assumption it is the constant flux equilibrium IMPOSED by the Stefan Boltzmann Law Mother Nature s Laws of Physics and seen on a daily basis The SBL Feedback which is dependant ONLY on the temperature and not the CO2 concentration cancels out the GHE temperature effect basically eliminating it as it occurs No GHE means no GHG CO2 induced warming as you said The ever increasing GHG Forcing Curve Planetary energy imbalance May 2005 IPCC is effectively a flatline Any research based on the increasing GHG forcing and the GCMs is invalid The estimates of the temperature impact of doubling the CO2 levels in the next century are just plain wrong This does not mean that global warming does not exist or that adding CO2 does not cause problems such as ocean acidification The evidence in melting polar ice caps glaciers and measured temperatures etc is too obvious However the increases must come from an external increase in energy in or maybe if the solar increases do not explain it some of the decreasing Earth magnetic field flux energy is leaking into the ground air Are we seeing increases in

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  • The Physics of Climate Modelling « RealClimate
    system i e using a model to predict what another run of the same model produced you can show that there is useful information in ocean initial conditions for about a decade mostly based on the North Atlantic However in the presence of strong forcing rising greenhouse gases volcanoes etc the predictions become much less dependent on the start So for the 20th century trends where we have essentially no information about the ocean initial conditions it is easy to see that the global trends even over decadal to multi decadal time scales are robust to the starting fields Skill in prediciting regional changes however even in a perfect set up is not very high mainly because of the amount of unforced weather noise which neither kind of prediction can capture gavin 11 CobblyWorlds says 6 Jan 2007 at 4 08 AM Re 8 No Alastair The CC net information page was as implied an addition for other interested amateur readers I ve not run any climate models merely read papers Were I to run a climate model I don t know I d have the skills to be sure whether it had correctly produced such a thing as the ITCZ 12 Barton Paul Levenson says 6 Jan 2007 at 12 44 PM Re The idea that mankind s small percentage of the carbon cycle could be the cause of the Mauna Loa graph seems to this layman to be unlikely the attribution owing more to man s overwheening vanity than scientific measurement like claiming the Earth as the centre of all things From 1750 or so to 2005 the ambient CO2 concentration rose from about 280 parts per million by volume to 380 ppmv We know it s from fossil fuel burning because we can measure the fraction of C14 and that has been declining There s virtually no CO2 left in old fossil fuels simply because their age is many times greater than the C14 half life This is the smoking gun that shows the CO2 is anthropogenic and not from some natural process All the CO2 in the biosphere has roughly the same mean level of C14 13 James says 6 Jan 2007 at 2 21 PM Also the amounts of fossil fuels used in the last century are quite well known you can look up the numbers in various economic statistical sources and from that you can easily compute how much CO2 was produced Add that up compare it to the observed increase and you ll find the numbers match Actually the amount of CO2 from fossil fuels is somewhat greater than the observed atmospheric increase because some gets dissolved in the ocean and so on Thinking of fossil fuel CO2 as man s small percentage is the wrong way to look at the problem The key word there is cycle all the rest with small exceptions like volcanic sources and geological sequestration is in a cycle that keeps going around and around The fossil fuel CO2 is an addition That addition may be comparatively small in any one year but it doesn t go away it keeps adding up 14 David Price says 6 Jan 2007 at 3 13 PM One question Have models taken in to account the increace in the number of thunderstorms that will result from warming I read once that thunderstorms keep the earth several degrees cooler than it would otherwise be As more storms happen the hotter it gets will they have a moderating impact Response Equilibrium requires a balance between downward and upward transport of energy within the atmosphere Thunderstorms should be thought of as simply one of many modes of behavior by which the atmosphere attempts to achieve this balance in this case largely through the vertical transport of latent heat associated with condensation of water vapor within storm clouds Obviously individual thunderstorms cannot be represented at the coarse spatial scales resolved by GCMs However their principal role in terms of energy balance as described above is represented in models through the parameterization of convective instability in the atmosphere Mike 15 mzed says 6 Jan 2007 at 11 09 PM 12 think you meant There s virtually no C14 left in old fossil fuels 16 Barton Paul Levenson says 7 Jan 2007 at 8 02 AM Re 12 think you meant There s virtually no C14 left in old fossil fuels Yep you ve got it My bad 17 Julian Flood says 7 Jan 2007 at 12 00 PM Re 5 Thank you for your reference I ve not replied to thank you until now because I ve been thinking Your reference is dated 1996 and as such the author had no access to the work was it by Morel et al I ve looked at so many abstracts today my gyros are toppled about C4 and beta carboxylation pathways in phytoplankton Under stress some phytos change from C3 metabolism and the isotopic fractions they sequester change the heavier molecules are not discriminated against so strongly So my ocean pollution hypothesis is up to this objection reduced upwelling and lessened entrainment of the surface by wind results in depleted zinc and cadmium levels Stressed the plankton switches to C4 beta carb and begins to rain out C13 enriched detritus depleting relatively the upper ocean of C13 in an isotopic refinment of the biological pump The ratio of C12 rises The normal process of mixing ensures that the air and water concentrations of the new isotopic balanced CO2 mix and match The atmosphere exhibits depleted C12 Surface pollution is worse in the Northern hemisphere and continued healthy upwelling in the Southern hemisphere helped by being less complicated by contraints of narrow seas means that the phytos there are less stressed and can continue their usual C3 way of life How then should an oceanic CO2 source cause a simultaneous drop of 13C in both the atmosphere and ocean Not a source A relative sink for C13 ref 13 the numbers match Have I got this wrong I ve seen references that half of the anthropogenic carbon is sequestered Half is not what I call a very good match However I d be grateful for references which tie this down a little more strongly as I m sure the science does not depend on a simple post hoc argument and I d like reassurance ref 12 The smoking gun indeed If a plant switches to C4 metabolism a technique which apparently is less discriminatory between C12 and C13 would it also sequester unexpected amounts of C14 Presumably the differences are purely mechanical which would indicate this was so Does anyone know If C14 is being used up unexpectedly what does this do to the smoking gun Maybe I need to think some more There should be some testable predictions from this C14 levels in deep sediments should show increases from around 1850 as the stressed oceans began to react to the outward spewing of the nascent petrochemical industry Plankton samples if dead maybe frozen should show a lack of zinc and cadmium indicating that they have changed to different metabolic systems Is the data already out there I leave other tests to the intelligent reader JF 18 Hank Roberts says 7 Jan 2007 at 1 09 PM I ve been wondering where to look for the surprises One example much belabored is methane hydrates I see that only a few years ago geologists were still debating the origin of pingos not the Linux penguin This is fossil carbon too presumably depleted of C14 Is there any clear idea how and when the stuff is formed I can imagine it could be either a cyclical process associated with glaciation lower temperature at a given depth below sea level or contrariwise when the planet is warmer CO2 higher and sea level much higher because pressure is greater at that same location I wonder if the models state an assumption about this stuff either it s been locked down by past extremes so is stable or it s at an equilibrium state so released as warming proceeds in local spikes as brief temperature extremes occur in the location I d think that some would have bubbled out over the last geologically brief warmth at end of last ice age but that would have been almost done happening as the planet slowly cooled back toward the next ice age The big old ones look like hills tree covered I wonder if the Navy has mapped the polar sea floor well enough to count undersea pingos presumably secret if so as detailed maps but if so perhaps summary data on size and location would be interesting to try to quantify what s been happening As of 2003 the origin of pingo structures was apparently still being debated lots of good pictures for example here http www mbari org news news releases 2003 paull pingos html Now it appears clear as they re being observed below sea level that they do form as methane boils off Is there enough info developing to include this in models 19 Jason Goodell says 7 Jan 2007 at 2 45 PM After reading this months quick study on climate modeling in Physics Today I ve been unable to push this topic from my mind especially with it being nearly 70 F here in New England yesterday As a physicist with only a casual understanding of the issues surrounding global climate change I m drawn to the simple idea that humanities demand for energy is the central issue As the global population inceases and the spread of technology increases the demand for energy generation will also increase For our great grandchildren other factors like thermal polution and the effects of large scale solar and wind farms may be the climate issue of their era CO2 emissions are only the beginning of what will be a constant need for the consideration of our actions and their impact on Earth s climate 20 Julian Flood says 8 Jan 2007 at 4 52 AM Sorry typo in 17 in spite of lots of thinking It should read of course the atmosphere exhibits depleted C13 not C12 Sorry about that It has me wondering about the mismatch of CO2 rising after temperature in the historical records do the dating techniques depend on C14 levels and would C4 reduction of C14 pull the dates back into line JF 21 Alastair McDonald says 8 Jan 2007 at 10 03 AM Re 20 etc Julian Gavin s reference was to a FAQ produces by Jan Schloerer of Ulm University and hosted on the web by Dr Robert Grumbine of NOAA http www radix net bobg Although the article is now over ten years old it directly answers your question one that has been asked by global warming skeptics for all those years Jan wrote From its preindustrial level of about 280 ppmv parts per million by volume around the year 1800 atmospheric carbon dioxide rose to 315 ppmv in 1958 and to about 358 ppmv in 1994 If you go to the Mauna Loa site you can see that it has continued to rise since then to about 375 ppmv in 2004 http cdiac ornl gov trends co2 graphics mlo145e thrudc04 pdf There is no doubt that the increase is due to fossil fuel burning You only have to think about about 100 million Americans taking their cars onto the road and burning on average one gallon of fuel each day That is 500 000 000 tons of CO2 they are producing per day Globally we have put a trillion tons Pt of CO2 into the atmosphere See http cdiac ornl gov trends emis tre glob htm 305 Gt of C equals 305 44 12 1 122 Pt Well that s what 6 5 billion little unassuming people can do if you give them enough time 22 Hank Roberts says 8 Jan 2007 at 11 46 AM C12 C13 C14 All three contribute The 14C 12C and 13C 12C ratios SCIENCE VOL 279 20 FEBRUARY 1998 1187 Atmospheric Radiocarbon Calibration to 45 000 yr B P Late Glacial Fluctuations and Cosmogenic Isotope Production 23 Charles Muller says 8 Jan 2007 at 11 51 AM About parametrization In your text Gavin you explain equation approximated physics eg radiative transfer and empirically based physics eg evaporation need for parametrization That s not really clear for a non expert do you mean for example that different coefficients of equations for these phenomena are to be regularly corrected from real world measurements and retrovalidation About emergence You say on one hand that large scale behaviors of climate are robust but on the other hand that they emerge from small scale and more chaotic features Does it mean that chaotic small scale behaviors of climate are after all without real concern for the accuracy of 2100 projection 24 Julian Flood says 8 Jan 2007 at 12 01 PM Re 21 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr I wonder why we assume that the C accumulating in the atmosphere is actually our C Why is there this tiny fraction of the overall flux which is not consumed The smoking gun did indicate that it s ex fossil fuel carbon because it is depleted in C14 as one would expect If C4 metabolism is disturbing the expected C14 levels then the bets are off The deep sea reservoir of C is 380 000 Gt Thinking non anthropocentrically why does our little flow go straight into the atmosphere Does it Obviously not because some of it gets lost Our flow is dwarfed by natural processes and we need to find a way of pointing at our emissions and proving that the trouble is what we re up to Otherwise we re like a little boy peeing into a lake and taking the blame when the dam bursts There s a sawtooth daily pattern to the Mauna Loa graph Is there any difference in the gas make up between day and night Does the isotopic makeup vary JF 25 Bryan Sralla says 8 Jan 2007 at 12 07 PM Re 10 Gavin thank you for responding Since a climate prediction problem of the first kind controlled by initial values will effect numerous non linear feedbacks which ultimately will effect the degree of free variations in the climate trajectories it seems well founded to me that many classes of climate prediction problems are controlled by intial values Do you agree with my statement Also greater numbers of non linear type feedbacks added to the AOGCMs will most likely increase the degrees of free variations in modeling experiments Right It then seems feasible that improving the models making them better resemble the real thing may make skillful multi decadal predictions more contolled by initial values not less since the amount of noise in the system is greater relative to the forced variations Since a boundary values problem is superimposed over the initial values problem in real climate prediction it seems necessary to obtain solutions which satisfy both types of equations for many climate prediction problems I think for some casual observers it might seem non intuitive that improving the models adds to more uncertainty in predictions The more I read and study the problem the more I am pursuaded you modelers have a tough problem on your hands Good luck 26 yartrebo says 8 Jan 2007 at 12 49 PM Re 24 Those single celled organisms are releasing carbon that was only recently fixed Even in the short term 1 year period it is within 1 of being in equilibrium with carbon fixed by life The C4 pathway is only used by grasses Other plants and all bacteria and protozoa use the older C3 pathway An organism cannot just choose which pathway is wants to use Even if land use patterns have changed the ratio of C4 to C3 plants probably increased it because so much crop and livestock land is planted with grasses the effect will be quite minor as the carbon is released back into the atmosphere in short order As far as the deep sea reservoir of C goes don t forget that it takes thousands of years for the deep ocean to turn over and that while it is a reservoir it was more or less in equilibrium at 285 ppm CO2 and thus that carbon wasn t going anywhere With current CO2 levels the deep ocean is actually a net sink of CO2 absorbing a fairly significant share of our emissions With regards to the sawtooth daily pattern at Mauna Loa it s due to photosynthesis during the day and respiration during the night While there s probably a difference in the isotopic makeup it s probably pretty small Thinking non anthropocentrically why does our little flow go straight into the atmosphere Does it Obviously not because some of it gets lost Quite easy just look at a smokestack or exhaust pipe The CO2 literally goes straight into the atmosphere As far as what gets lost that s mostly the ocean absorbing about half of it It isn t gone for good and if CO2 levels drop the process will reverse releasing the CO2 back to the atmosphere 27 James says 8 Jan 2007 at 1 28 PM Re 24 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr Rather misleading language they don t push out that much CO2 except in the sense that you push out a certain amount of CO2 every time you exhale A better way to put it would be to say that they cycle through that much carbon it comes in it goes out but only if there is a change in the mass of soil organisms and their corpses etc does all that activity produce a net change in CO2 This does bring up a question I ve sometimes wondered about but have never seen numbers on suppose we could ignore the political obstacles and make a serious attempt at re vegetating areas the western US North Africa the Mideast Australia that have been desertified by human activity How much CO2 could we expect that to sequester 28 Hank Roberts says 8 Jan 2007 at 1 52 PM Julian here are papers addressing the questions you posed above just a couple from a large and interesting site You d want to check the citation index forward because these are relatively old papers not the current best info but a place to start There has been a lot of research addressing the questions you mention above and I am sure isn t news to the climate scientists It s an example of the details they have to consider http www igac noaa gov newsletter 16 co2 php Isotopomers of CO2 and their use in understanding the global carbon cycle One of the most striking results that 13C data and now O2 N2 ratio data unveiled is the existence of a very large repository of anthropogenic CO2 in Northern Hemisphere ecosystems during the early 1990 s when the atmospheric CO2 growth rate had diminished to only one third of its normal value Still the long term trend and interannual fluctuations of 13C at one given monitoring station is at the limit of detection of mass spectrometers on the order of 0 01 per mil for 13C in CO2 Thus even a very slight bias in the isotopic data would translate into different inferred magnitudes of the global land and ocean uptake of anthropogenic CO2 http www igac noaa gov newsletter 16 mass new php Biogenic aerosol formation in the boreal forest BIOFOR Anomalous or Not Strictly Mass Dependent Isotope Variations Observed in Important Atmospheric Trace Gases Variations in stable isotope ratios in the environment have generally been well understood and put to good use However the atmosphere appears to be the scene for a host of isotope effects that we do not yet understand The prime example is ozone whose anomalous enrichment has repeatedly defied correct interpretation Atmospheric studies also benefit from stable isotope variations An illustration is the ongoing decline of the 13C 12C ratio of atmospheric carbon dioxide largely in consequence of the increasing fraction of fossil fuel derived carbon dioxide This isotope effect is thus directly related to the isotopic composition of an important source of the gas Fossil fuels have about 2 less 13C than atmospheric carbon dioxide This in itself is obviously not a source effect ambient CO2 is the carbon source for plants but rather an isotope fractionation effect of photosynthesis Plants favor 12CO2 slightly over 13CO2 so the assimilated carbon is depleted in 13C relative to the atmosphere In isotope applications of interest to atmospheric chemistry source signatures and fractionation effects in chemical reactions are both relevant It has taken years to unravel the secrets of the anomalous isotope fractionation of ozone perhaps the most extensively studied reactive atmospheric trace gas In regard to molecular symmetry 17O and 18O in an ozone molecule are identical they are simply different from the abundant 16O isotope However theories based on symmetry have been challenged by the latest experimental data After ozone it was found that carbon dioxide in the stratosphere exhibits MIF Thiemens et al 1995 Gamo et al 1989 A chemical mechanism was proposed by Yung et al 1991 who showed that the observed 17O excess in CO2 could be explained by transfer of the enrichment present in ozone to CO2 via the excited oxygen radical 29 Hank Roberts says 8 Jan 2007 at 2 18 PM Another good source on where CO2 is coming from here dated early 2005 http www publish csiro au act view file file id EN05013 pdf Recent Record Growth inAtmospheric CO Levels Regrettably the actual data illuminating this question was collected at stations funded by the USA and Australia that are now being shut down the authors point out 30 Sally says 8 Jan 2007 at 4 01 PM Re 24 There s a sawtooth daily pattern to the Mauna Loa graph Is there any difference in the gas make up between day and night Does the isotopic makeup vary Is there a daily sawtooth pattern to the Mauna Loa graph There is certainly an annual sawtooth pattern caused by the northern hemisphere forests kicking in with photosynthesis every spring That is probably rather simplistic but I think it is what Charles Keeling set out to measure initially The carbon flux is affected by all photosynthesis terrestrial and aquatic There would be a daily flux however as plants respire all the time but only photosynthesize during light conditions Again this is a simple explanation and does not take into account the processes that go on in the dark to produce sugars If you go here http cdiac ornl gov trends co2 nocm htm you can look at graphs from the four collection stations at Barrow Alaska Samoa the south pole and Mauna Loa You will see from the graph found here http cdiac ornl gov trends co2 nocm sagr htm that there is far less fluctuation in Samoa as the climate has little seasonal change at this location I hope this helps 31 Donald G says 10 Jan 2007 at 5 26 PM I propose we invest massive resources into making a large array of petaflop scale computers dedicated to the study of global warming This way if the simulations show that Global Warming isn t an upcoming threat we ve ensured that it really is by churning out more than enough CO2 while making those computers 32 John Dodds says 10 Jan 2007 at 7 10 PM Re 24 30 Go to http meteo lcd lu today 01 html to see real live CO2 concentrations et al in Luxemburg Variations over 50 and as high as 500 ppm I agree that the patterns are complex Just changing the water vapor content rainstorms plays havoc with the CO2 concentrations as does the daily commute vehicle exhaust near the measuring station In general it is my understanding that the daily fluctuaions even the yearly cycle have a relatively small impact on the global warming consequences I think there is a Gavin comment to this effect from a year or so ago somewhere in the archives 33 Alastair McDonald says 10 Jan 2007 at 7 20 PM Re 24 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr Yes and they are better at sequestering carbon than us too They absorb 60 GtC yr too That is the oscillation you though were daily but are actually yearly We are what is making the curve rise 34 English says 12 Jan 2007 at 5 11 PM The text has both punctuation errors and errors of grammar Some of these errors are not insognificant The text of the document can be seen as ambiguous I would most respectfuly suggest that any text be checked for errors in grammar and punctuation by a technical author prior to publication Response Bit late now but what specifically did you find ambiguous gavin 35 Julian Flood says 13 Jan 2007 at 8 29 AM re 28 thanks for the sites even more thinking needed I read a recent CO2 metabolism paper for a particular species of phytoplankton and began to wonder about the chance that they are less consistent than science currently understands If the knowledge that certain marine plants can swap between C3 and C4 is only about 5 years old I d rather like to see whether their different fixation routes do odd things to oxygen isotope ratios There is a rather disturbing illo of the degree of confidence in the science of global warming low low and very low occur too often to be reassuring Governments make a lot of noise about global warming how odd that they don t throw large amounts of money to the only people who can demonstrate by scientific measurement exactly what s happening And yet monitoring sites are being abandoned why is that Do governments know something or is it merely complacency 30 thank you There s a daily wiggle rather than an annual sawtooth I believe but you re right I was conflating the two I m wondering if a signal of isotopic fractionisation could be teased out of the daily signal pinning it down to either worldwide or near ocean effects If the ocean surface pollution hypothesis of global warming is correct then this is the sequence the petrochemical industry kicks into life around 1850 Surfactant run off and oil spill begin to reduce stratocumulus cover the whole surface of the ocean warms reducing nutrient upflows and encouraging the phytoplankton to kick into C4 metabolism C4 phytoplankton increase in numbers as their relative advantage inproves over C3 plants C4 plankton sequesters more C13 than expected by conventional models expected levels of C13 fall producing a false anthropogenic signal Surfactant and oil pollution effects increase CO2 levels by reducing biological pull down mechanical mixing and reduce solubility by warming the surface What happens to the albedo of a polluted surface I don t know Deep water warms slightly Methanophages begin to emit more light isotope CO2 as the clathrate deposits become more accessible CO2 warming increases The ocean surface becomes even more stable and the cycle continues Eventually the clathrates boil off Result large temperature spike and collapse of civilisation I wonder if there s anything in the fossil record which would fit this scenario triggered perhaps by the breaching of a large light oil reservoir by coastal erosion I wonder what signals a scenario like that would leave for us to interpret Well I like it better than a convenient volcano boiling off a carbon deposit JF 36 Peter Erwin says 15 Jan 2007 at 4 30 AM Re 27 This does bring up a question I ve sometimes wondered about but have never seen numbers on suppose we could ignore the political obstacles and make a serious attempt at re vegetating areas the western US North Africa the Mideast Australia that have been desertified by human activity Most of those areas have not been desertified by human activity they re naturally deserts part of the global desert belts at low latitudes Vegetating them on a large scale would probably require significant energy expenditures and accompanying CO2 release for fertilization water transport and building the necessary infrastructure This is not to say that it s a bad idea to reverse desertification in local areas where it s recently occured of course 37 Alastair McDonald says 15 Jan 2007 at 9 16 AM Re 35 Julian there is a major event in the fossil record called the PETM Paleocene Eocene Thermal Maximum See http www es ucsc edu silab biocomplex lptm background htm 38 John Dodds says 16 Jan 2007 at 7 58 AM From the various Hansen et al and other papers the computer calculations of global warming show that adding CO2 results in the added CO2 molecules delaying not trapping the transport of energy out of the earth system and the subsequent global warming of the air near the ground and cooling near the top of the atmosphere TOA see cartoon figure 2e from Hansen et al 2005 This is the Greenhouse Effect The global warming effects results in a positive energy imbalance or disequilibrium at the TOA where more solar energy is coming in than is being sent out because the TOA temperature is colder than the equilibrium This apparently lasts for years if not forever per the GCMs Hansen Nazarenko et al 2005 However on a daily basis the Earth goes through a daily rotating solar cycle where at night we have a negative imbalance with more energy out than in then as the sun rises we warm up pass through the equilibrium point to get a positive imbalance and stay that way until the sun again starts to set and the energy in again passes through the equilibrium point and we return to a negative imbalance The same process happens when we get yearly seasonal temperature cycles and also on the approximately 11 year solar energy cycles which change the energy in amounts At all times the amount of energy being transported out of the Earth system is calculated by the Stefan Boltzmann Law SBL based ONLY on the temperature of the Earth system be it at the ground or at the TOA The SBL which says that the energy transported from an object is proportional to the temperature raised to the 4th power ie hotter air rises faster convection or hotter objects radiate more energy per unit time radiation transport is forever trying to reestablish the earth to its equilibrium energy in equals energy out conditions by either warming or cooling it and it is perfectly successful exactly twice each and every day This contradicts the conclusions of the Global Computer Models GCMs which require a permanent or multi decade disequilibrium or energy imbalance to create the global warming So the question is WHY doesn t the Stefan Boltzman Law feedback also automatically compensate for the greenhouse effect Why doesn t the feedback from the SBL automatically return the air to its equilibrium to solar energy in conditions imposed by the daily solar cycles Why isn t the delay in energy transport by adding GHGs compensated for by the speedup in radiation transport at the speed of light caused by the increase in temperature and the SBL response The SBL has no way of differentiating between a GHG or solar caused warming According to the GCMs we already know that the CO2 caused global warming results in hotter air rising faster convection at ground level which Gavin says is included in the GCMs as a part of the water vapor feedback effect How not to attribute climate change comment 182 12 57 pm see also 126 et seq 208 Why doesn t the hotter air at ground level also cause more energy to be radiated out faster per the SBL to result in the greenhouse caused warming energy to be returned to the TOA where the extra energy will cancel out the CO2 caused imbalance at the TOA ie to return the Earth to its equilibrium conditions which it actually does twice a day The conventional wisdom that greenhouse gases cause global warming is based on the identification of the greenhouse effect GHE in the Svante Arrhenius 1896 paper see Wikipedia On the Influence of Carbonic Acid in the Air Upon the Temperature of the Ground However my simple reading of the paper shows that Arrhenius calculated the warming effect of CO2 energy absorption in academic isolation CO2 absorbs energy without considering the real world effects of the Stefan Boltzmann Law Feedback Also a review of the Global Computer Models GCMs results shows that the amount of global warming calculated varies depending upon the duration of the period modeled eg 1950 1997 1880 2000 1750 2000 or from the bottom of the ice age and bottom of the CO2 level 20 000 years ago until 2000 etc This is to be expected except that the computer model also requires that the temperature imbalance at the TOA be equal to and opposite the warming to maintain conservation of energy SO just what is the temperature at the TOA in the year 2000 It HAS to be a single value not the infinite number of options that can result from the GCMs Again the GCMs are calculating results that are not possible BUT if the SBL Feedback returns the TOA to the equilibrium conditions then we have a single value but then there is no energy imbalance However there also is no global warming due to the GHE Sorry Gavin but I feel that the GCMs are giving such fundamentally incorrect inconsistent results that they can NOT be valid They seem to be missing some of the SBL feedback If you can explain these discrepancies please do Which brings us back to what you previously stated 15 months ago Response You refuse to relax your incorrect assumption that the flux from the surface is the same as the flux from the top of the atmosphere which is equivalent to assuming that there is no GHE at all So you assume the result you wish to prove gavin Comment by John Dodds 30 Oct 2005 8 04 pm click on the time stamp to go to Gavin Schmidt s RealClimate org location To which I now respond Yes Gavin I intuitively assumed constant equilibrium flux but it is not my assumption it is the constant flux equilibrium IMPOSED by the Stefan Boltzmann Law Mother Nature s Laws of Physics and seen on a daily basis The SBL Feedback which is dependant ONLY on the temperature and not the CO2 concentration cancels out the GHE temperature effect basically eliminating it as it occurs No GHE means no GHG CO2 induced warming as you said The ever increasing GHG Forcing Curve Planetary energy imbalance May 2005 IPCC is effectively a flatline Any research based on the increasing GHG forcing and the GCMs is invalid The estimates of the temperature impact of doubling the CO2 levels in the next century are just plain wrong This does not mean that global warming does not exist or that adding CO2 does not cause problems such as ocean acidification The evidence in melting polar ice caps glaciers and measured temperatures etc is too obvious However the increases must come from an external increase in energy in or maybe if the solar increases do not explain it some of the decreasing Earth magnetic field flux energy is leaking into the ground air Are we seeing increases in the northern

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    thinking on this Response Practically you can distinguish between the two types just by seeing whether the initial conditions matter In a perfect system i e using a model to predict what another run of the same model produced you can show that there is useful information in ocean initial conditions for about a decade mostly based on the North Atlantic However in the presence of strong forcing rising greenhouse gases volcanoes etc the predictions become much less dependent on the start So for the 20th century trends where we have essentially no information about the ocean initial conditions it is easy to see that the global trends even over decadal to multi decadal time scales are robust to the starting fields Skill in prediciting regional changes however even in a perfect set up is not very high mainly because of the amount of unforced weather noise which neither kind of prediction can capture gavin 11 CobblyWorlds says 6 Jan 2007 at 4 08 AM Re 8 No Alastair The CC net information page was as implied an addition for other interested amateur readers I ve not run any climate models merely read papers Were I to run a climate model I don t know I d have the skills to be sure whether it had correctly produced such a thing as the ITCZ 12 Barton Paul Levenson says 6 Jan 2007 at 12 44 PM Re The idea that mankind s small percentage of the carbon cycle could be the cause of the Mauna Loa graph seems to this layman to be unlikely the attribution owing more to man s overwheening vanity than scientific measurement like claiming the Earth as the centre of all things From 1750 or so to 2005 the ambient CO2 concentration rose from about 280 parts per million by volume to 380 ppmv We know it s from fossil fuel burning because we can measure the fraction of C14 and that has been declining There s virtually no CO2 left in old fossil fuels simply because their age is many times greater than the C14 half life This is the smoking gun that shows the CO2 is anthropogenic and not from some natural process All the CO2 in the biosphere has roughly the same mean level of C14 13 James says 6 Jan 2007 at 2 21 PM Also the amounts of fossil fuels used in the last century are quite well known you can look up the numbers in various economic statistical sources and from that you can easily compute how much CO2 was produced Add that up compare it to the observed increase and you ll find the numbers match Actually the amount of CO2 from fossil fuels is somewhat greater than the observed atmospheric increase because some gets dissolved in the ocean and so on Thinking of fossil fuel CO2 as man s small percentage is the wrong way to look at the problem The key word there is cycle all the rest with small exceptions like volcanic sources and geological sequestration is in a cycle that keeps going around and around The fossil fuel CO2 is an addition That addition may be comparatively small in any one year but it doesn t go away it keeps adding up 14 David Price says 6 Jan 2007 at 3 13 PM One question Have models taken in to account the increace in the number of thunderstorms that will result from warming I read once that thunderstorms keep the earth several degrees cooler than it would otherwise be As more storms happen the hotter it gets will they have a moderating impact Response Equilibrium requires a balance between downward and upward transport of energy within the atmosphere Thunderstorms should be thought of as simply one of many modes of behavior by which the atmosphere attempts to achieve this balance in this case largely through the vertical transport of latent heat associated with condensation of water vapor within storm clouds Obviously individual thunderstorms cannot be represented at the coarse spatial scales resolved by GCMs However their principal role in terms of energy balance as described above is represented in models through the parameterization of convective instability in the atmosphere Mike 15 mzed says 6 Jan 2007 at 11 09 PM 12 think you meant There s virtually no C14 left in old fossil fuels 16 Barton Paul Levenson says 7 Jan 2007 at 8 02 AM Re 12 think you meant There s virtually no C14 left in old fossil fuels Yep you ve got it My bad 17 Julian Flood says 7 Jan 2007 at 12 00 PM Re 5 Thank you for your reference I ve not replied to thank you until now because I ve been thinking Your reference is dated 1996 and as such the author had no access to the work was it by Morel et al I ve looked at so many abstracts today my gyros are toppled about C4 and beta carboxylation pathways in phytoplankton Under stress some phytos change from C3 metabolism and the isotopic fractions they sequester change the heavier molecules are not discriminated against so strongly So my ocean pollution hypothesis is up to this objection reduced upwelling and lessened entrainment of the surface by wind results in depleted zinc and cadmium levels Stressed the plankton switches to C4 beta carb and begins to rain out C13 enriched detritus depleting relatively the upper ocean of C13 in an isotopic refinment of the biological pump The ratio of C12 rises The normal process of mixing ensures that the air and water concentrations of the new isotopic balanced CO2 mix and match The atmosphere exhibits depleted C12 Surface pollution is worse in the Northern hemisphere and continued healthy upwelling in the Southern hemisphere helped by being less complicated by contraints of narrow seas means that the phytos there are less stressed and can continue their usual C3 way of life How then should an oceanic CO2 source cause a simultaneous drop of 13C in both the atmosphere and ocean Not a source A relative sink for C13 ref 13 the numbers match Have I got this wrong I ve seen references that half of the anthropogenic carbon is sequestered Half is not what I call a very good match However I d be grateful for references which tie this down a little more strongly as I m sure the science does not depend on a simple post hoc argument and I d like reassurance ref 12 The smoking gun indeed If a plant switches to C4 metabolism a technique which apparently is less discriminatory between C12 and C13 would it also sequester unexpected amounts of C14 Presumably the differences are purely mechanical which would indicate this was so Does anyone know If C14 is being used up unexpectedly what does this do to the smoking gun Maybe I need to think some more There should be some testable predictions from this C14 levels in deep sediments should show increases from around 1850 as the stressed oceans began to react to the outward spewing of the nascent petrochemical industry Plankton samples if dead maybe frozen should show a lack of zinc and cadmium indicating that they have changed to different metabolic systems Is the data already out there I leave other tests to the intelligent reader JF 18 Hank Roberts says 7 Jan 2007 at 1 09 PM I ve been wondering where to look for the surprises One example much belabored is methane hydrates I see that only a few years ago geologists were still debating the origin of pingos not the Linux penguin This is fossil carbon too presumably depleted of C14 Is there any clear idea how and when the stuff is formed I can imagine it could be either a cyclical process associated with glaciation lower temperature at a given depth below sea level or contrariwise when the planet is warmer CO2 higher and sea level much higher because pressure is greater at that same location I wonder if the models state an assumption about this stuff either it s been locked down by past extremes so is stable or it s at an equilibrium state so released as warming proceeds in local spikes as brief temperature extremes occur in the location I d think that some would have bubbled out over the last geologically brief warmth at end of last ice age but that would have been almost done happening as the planet slowly cooled back toward the next ice age The big old ones look like hills tree covered I wonder if the Navy has mapped the polar sea floor well enough to count undersea pingos presumably secret if so as detailed maps but if so perhaps summary data on size and location would be interesting to try to quantify what s been happening As of 2003 the origin of pingo structures was apparently still being debated lots of good pictures for example here http www mbari org news news releases 2003 paull pingos html Now it appears clear as they re being observed below sea level that they do form as methane boils off Is there enough info developing to include this in models 19 Jason Goodell says 7 Jan 2007 at 2 45 PM After reading this months quick study on climate modeling in Physics Today I ve been unable to push this topic from my mind especially with it being nearly 70 F here in New England yesterday As a physicist with only a casual understanding of the issues surrounding global climate change I m drawn to the simple idea that humanities demand for energy is the central issue As the global population inceases and the spread of technology increases the demand for energy generation will also increase For our great grandchildren other factors like thermal polution and the effects of large scale solar and wind farms may be the climate issue of their era CO2 emissions are only the beginning of what will be a constant need for the consideration of our actions and their impact on Earth s climate 20 Julian Flood says 8 Jan 2007 at 4 52 AM Sorry typo in 17 in spite of lots of thinking It should read of course the atmosphere exhibits depleted C13 not C12 Sorry about that It has me wondering about the mismatch of CO2 rising after temperature in the historical records do the dating techniques depend on C14 levels and would C4 reduction of C14 pull the dates back into line JF 21 Alastair McDonald says 8 Jan 2007 at 10 03 AM Re 20 etc Julian Gavin s reference was to a FAQ produces by Jan Schloerer of Ulm University and hosted on the web by Dr Robert Grumbine of NOAA http www radix net bobg Although the article is now over ten years old it directly answers your question one that has been asked by global warming skeptics for all those years Jan wrote From its preindustrial level of about 280 ppmv parts per million by volume around the year 1800 atmospheric carbon dioxide rose to 315 ppmv in 1958 and to about 358 ppmv in 1994 If you go to the Mauna Loa site you can see that it has continued to rise since then to about 375 ppmv in 2004 http cdiac ornl gov trends co2 graphics mlo145e thrudc04 pdf There is no doubt that the increase is due to fossil fuel burning You only have to think about about 100 million Americans taking their cars onto the road and burning on average one gallon of fuel each day That is 500 000 000 tons of CO2 they are producing per day Globally we have put a trillion tons Pt of CO2 into the atmosphere See http cdiac ornl gov trends emis tre glob htm 305 Gt of C equals 305 44 12 1 122 Pt Well that s what 6 5 billion little unassuming people can do if you give them enough time 22 Hank Roberts says 8 Jan 2007 at 11 46 AM C12 C13 C14 All three contribute The 14C 12C and 13C 12C ratios SCIENCE VOL 279 20 FEBRUARY 1998 1187 Atmospheric Radiocarbon Calibration to 45 000 yr B P Late Glacial Fluctuations and Cosmogenic Isotope Production 23 Charles Muller says 8 Jan 2007 at 11 51 AM About parametrization In your text Gavin you explain equation approximated physics eg radiative transfer and empirically based physics eg evaporation need for parametrization That s not really clear for a non expert do you mean for example that different coefficients of equations for these phenomena are to be regularly corrected from real world measurements and retrovalidation About emergence You say on one hand that large scale behaviors of climate are robust but on the other hand that they emerge from small scale and more chaotic features Does it mean that chaotic small scale behaviors of climate are after all without real concern for the accuracy of 2100 projection 24 Julian Flood says 8 Jan 2007 at 12 01 PM Re 21 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr I wonder why we assume that the C accumulating in the atmosphere is actually our C Why is there this tiny fraction of the overall flux which is not consumed The smoking gun did indicate that it s ex fossil fuel carbon because it is depleted in C14 as one would expect If C4 metabolism is disturbing the expected C14 levels then the bets are off The deep sea reservoir of C is 380 000 Gt Thinking non anthropocentrically why does our little flow go straight into the atmosphere Does it Obviously not because some of it gets lost Our flow is dwarfed by natural processes and we need to find a way of pointing at our emissions and proving that the trouble is what we re up to Otherwise we re like a little boy peeing into a lake and taking the blame when the dam bursts There s a sawtooth daily pattern to the Mauna Loa graph Is there any difference in the gas make up between day and night Does the isotopic makeup vary JF 25 Bryan Sralla says 8 Jan 2007 at 12 07 PM Re 10 Gavin thank you for responding Since a climate prediction problem of the first kind controlled by initial values will effect numerous non linear feedbacks which ultimately will effect the degree of free variations in the climate trajectories it seems well founded to me that many classes of climate prediction problems are controlled by intial values Do you agree with my statement Also greater numbers of non linear type feedbacks added to the AOGCMs will most likely increase the degrees of free variations in modeling experiments Right It then seems feasible that improving the models making them better resemble the real thing may make skillful multi decadal predictions more contolled by initial values not less since the amount of noise in the system is greater relative to the forced variations Since a boundary values problem is superimposed over the initial values problem in real climate prediction it seems necessary to obtain solutions which satisfy both types of equations for many climate prediction problems I think for some casual observers it might seem non intuitive that improving the models adds to more uncertainty in predictions The more I read and study the problem the more I am pursuaded you modelers have a tough problem on your hands Good luck 26 yartrebo says 8 Jan 2007 at 12 49 PM Re 24 Those single celled organisms are releasing carbon that was only recently fixed Even in the short term 1 year period it is within 1 of being in equilibrium with carbon fixed by life The C4 pathway is only used by grasses Other plants and all bacteria and protozoa use the older C3 pathway An organism cannot just choose which pathway is wants to use Even if land use patterns have changed the ratio of C4 to C3 plants probably increased it because so much crop and livestock land is planted with grasses the effect will be quite minor as the carbon is released back into the atmosphere in short order As far as the deep sea reservoir of C goes don t forget that it takes thousands of years for the deep ocean to turn over and that while it is a reservoir it was more or less in equilibrium at 285 ppm CO2 and thus that carbon wasn t going anywhere With current CO2 levels the deep ocean is actually a net sink of CO2 absorbing a fairly significant share of our emissions With regards to the sawtooth daily pattern at Mauna Loa it s due to photosynthesis during the day and respiration during the night While there s probably a difference in the isotopic makeup it s probably pretty small Thinking non anthropocentrically why does our little flow go straight into the atmosphere Does it Obviously not because some of it gets lost Quite easy just look at a smokestack or exhaust pipe The CO2 literally goes straight into the atmosphere As far as what gets lost that s mostly the ocean absorbing about half of it It isn t gone for good and if CO2 levels drop the process will reverse releasing the CO2 back to the atmosphere 27 James says 8 Jan 2007 at 1 28 PM Re 24 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr Rather misleading language they don t push out that much CO2 except in the sense that you push out a certain amount of CO2 every time you exhale A better way to put it would be to say that they cycle through that much carbon it comes in it goes out but only if there is a change in the mass of soil organisms and their corpses etc does all that activity produce a net change in CO2 This does bring up a question I ve sometimes wondered about but have never seen numbers on suppose we could ignore the political obstacles and make a serious attempt at re vegetating areas the western US North Africa the Mideast Australia that have been desertified by human activity How much CO2 could we expect that to sequester 28 Hank Roberts says 8 Jan 2007 at 1 52 PM Julian here are papers addressing the questions you posed above just a couple from a large and interesting site You d want to check the citation index forward because these are relatively old papers not the current best info but a place to start There has been a lot of research addressing the questions you mention above and I am sure isn t news to the climate scientists It s an example of the details they have to consider http www igac noaa gov newsletter 16 co2 php Isotopomers of CO2 and their use in understanding the global carbon cycle One of the most striking results that 13C data and now O2 N2 ratio data unveiled is the existence of a very large repository of anthropogenic CO2 in Northern Hemisphere ecosystems during the early 1990 s when the atmospheric CO2 growth rate had diminished to only one third of its normal value Still the long term trend and interannual fluctuations of 13C at one given monitoring station is at the limit of detection of mass spectrometers on the order of 0 01 per mil for 13C in CO2 Thus even a very slight bias in the isotopic data would translate into different inferred magnitudes of the global land and ocean uptake of anthropogenic CO2 http www igac noaa gov newsletter 16 mass new php Biogenic aerosol formation in the boreal forest BIOFOR Anomalous or Not Strictly Mass Dependent Isotope Variations Observed in Important Atmospheric Trace Gases Variations in stable isotope ratios in the environment have generally been well understood and put to good use However the atmosphere appears to be the scene for a host of isotope effects that we do not yet understand The prime example is ozone whose anomalous enrichment has repeatedly defied correct interpretation Atmospheric studies also benefit from stable isotope variations An illustration is the ongoing decline of the 13C 12C ratio of atmospheric carbon dioxide largely in consequence of the increasing fraction of fossil fuel derived carbon dioxide This isotope effect is thus directly related to the isotopic composition of an important source of the gas Fossil fuels have about 2 less 13C than atmospheric carbon dioxide This in itself is obviously not a source effect ambient CO2 is the carbon source for plants but rather an isotope fractionation effect of photosynthesis Plants favor 12CO2 slightly over 13CO2 so the assimilated carbon is depleted in 13C relative to the atmosphere In isotope applications of interest to atmospheric chemistry source signatures and fractionation effects in chemical reactions are both relevant It has taken years to unravel the secrets of the anomalous isotope fractionation of ozone perhaps the most extensively studied reactive atmospheric trace gas In regard to molecular symmetry 17O and 18O in an ozone molecule are identical they are simply different from the abundant 16O isotope However theories based on symmetry have been challenged by the latest experimental data After ozone it was found that carbon dioxide in the stratosphere exhibits MIF Thiemens et al 1995 Gamo et al 1989 A chemical mechanism was proposed by Yung et al 1991 who showed that the observed 17O excess in CO2 could be explained by transfer of the enrichment present in ozone to CO2 via the excited oxygen radical 29 Hank Roberts says 8 Jan 2007 at 2 18 PM Another good source on where CO2 is coming from here dated early 2005 http www publish csiro au act view file file id EN05013 pdf Recent Record Growth inAtmospheric CO Levels Regrettably the actual data illuminating this question was collected at stations funded by the USA and Australia that are now being shut down the authors point out 30 Sally says 8 Jan 2007 at 4 01 PM Re 24 There s a sawtooth daily pattern to the Mauna Loa graph Is there any difference in the gas make up between day and night Does the isotopic makeup vary Is there a daily sawtooth pattern to the Mauna Loa graph There is certainly an annual sawtooth pattern caused by the northern hemisphere forests kicking in with photosynthesis every spring That is probably rather simplistic but I think it is what Charles Keeling set out to measure initially The carbon flux is affected by all photosynthesis terrestrial and aquatic There would be a daily flux however as plants respire all the time but only photosynthesize during light conditions Again this is a simple explanation and does not take into account the processes that go on in the dark to produce sugars If you go here http cdiac ornl gov trends co2 nocm htm you can look at graphs from the four collection stations at Barrow Alaska Samoa the south pole and Mauna Loa You will see from the graph found here http cdiac ornl gov trends co2 nocm sagr htm that there is far less fluctuation in Samoa as the climate has little seasonal change at this location I hope this helps 31 Donald G says 10 Jan 2007 at 5 26 PM I propose we invest massive resources into making a large array of petaflop scale computers dedicated to the study of global warming This way if the simulations show that Global Warming isn t an upcoming threat we ve ensured that it really is by churning out more than enough CO2 while making those computers 32 John Dodds says 10 Jan 2007 at 7 10 PM Re 24 30 Go to http meteo lcd lu today 01 html to see real live CO2 concentrations et al in Luxemburg Variations over 50 and as high as 500 ppm I agree that the patterns are complex Just changing the water vapor content rainstorms plays havoc with the CO2 concentrations as does the daily commute vehicle exhaust near the measuring station In general it is my understanding that the daily fluctuaions even the yearly cycle have a relatively small impact on the global warming consequences I think there is a Gavin comment to this effect from a year or so ago somewhere in the archives 33 Alastair McDonald says 10 Jan 2007 at 7 20 PM Re 24 Simple one celled organisms in the soil are doing better than that they push out 60 GtC yr Yes and they are better at sequestering carbon than us too They absorb 60 GtC yr too That is the oscillation you though were daily but are actually yearly We are what is making the curve rise 34 English says 12 Jan 2007 at 5 11 PM The text has both punctuation errors and errors of grammar Some of these errors are not insognificant The text of the document can be seen as ambiguous I would most respectfuly suggest that any text be checked for errors in grammar and punctuation by a technical author prior to publication Response Bit late now but what specifically did you find ambiguous gavin 35 Julian Flood says 13 Jan 2007 at 8 29 AM re 28 thanks for the sites even more thinking needed I read a recent CO2 metabolism paper for a particular species of phytoplankton and began to wonder about the chance that they are less consistent than science currently understands If the knowledge that certain marine plants can swap between C3 and C4 is only about 5 years old I d rather like to see whether their different fixation routes do odd things to oxygen isotope ratios There is a rather disturbing illo of the degree of confidence in the science of global warming low low and very low occur too often to be reassuring Governments make a lot of noise about global warming how odd that they don t throw large amounts of money to the only people who can demonstrate by scientific measurement exactly what s happening And yet monitoring sites are being abandoned why is that Do governments know something or is it merely complacency 30 thank you There s a daily wiggle rather than an annual sawtooth I believe but you re right I was conflating the two I m wondering if a signal of isotopic fractionisation could be teased out of the daily signal pinning it down to either worldwide or near ocean effects If the ocean surface pollution hypothesis of global warming is correct then this is the sequence the petrochemical industry kicks into life around 1850 Surfactant run off and oil spill begin to reduce stratocumulus cover the whole surface of the ocean warms reducing nutrient upflows and encouraging the phytoplankton to kick into C4 metabolism C4 phytoplankton increase in numbers as their relative advantage inproves over C3 plants C4 plankton sequesters more C13 than expected by conventional models expected levels of C13 fall producing a false anthropogenic signal Surfactant and oil pollution effects increase CO2 levels by reducing biological pull down mechanical mixing and reduce solubility by warming the surface What happens to the albedo of a polluted surface I don t know Deep water warms slightly Methanophages begin to emit more light isotope CO2 as the clathrate deposits become more accessible CO2 warming increases The ocean surface becomes even more stable and the cycle continues Eventually the clathrates boil off Result large temperature spike and collapse of civilisation I wonder if there s anything in the fossil record which would fit this scenario triggered perhaps by the breaching of a large light oil reservoir by coastal erosion I wonder what signals a scenario like that would leave for us to interpret Well I like it better than a convenient volcano boiling off a carbon deposit JF 36 Peter Erwin says 15 Jan 2007 at 4 30 AM Re 27 This does bring up a question I ve sometimes wondered about but have never seen numbers on suppose we could ignore the political obstacles and make a serious attempt at re vegetating areas the western US North Africa the Mideast Australia that have been desertified by human activity Most of those areas have not been desertified by human activity they re naturally deserts part of the global desert belts at low latitudes Vegetating them on a large scale would probably require significant energy expenditures and accompanying CO2 release for fertilization water transport and building the necessary infrastructure This is not to say that it s a bad idea to reverse desertification in local areas where it s recently occured of course 37 Alastair McDonald says 15 Jan 2007 at 9 16 AM Re 35 Julian there is a major event in the fossil record called the PETM Paleocene Eocene Thermal Maximum See http www es ucsc edu silab biocomplex lptm background htm 38 John Dodds says 16 Jan 2007 at 7 58 AM From the various Hansen et al and other papers the computer calculations of global warming show that adding CO2 results in the added CO2 molecules delaying not trapping the transport of energy out of the earth system and the subsequent global warming of the air near the ground and cooling near the top of the atmosphere TOA see cartoon figure 2e from Hansen et al 2005 This is the Greenhouse Effect The global warming effects results in a positive energy imbalance or disequilibrium at the TOA where more solar energy is coming in than is being sent out because the TOA temperature is colder than the equilibrium This apparently lasts for years if not forever per the GCMs Hansen Nazarenko et al 2005 However on a daily basis the Earth goes through a daily rotating solar cycle where at night we have a negative imbalance with more energy out than in then as the sun rises we warm up pass through the equilibrium point to get a positive imbalance and stay that way until the sun again starts to set and the energy in again passes through the equilibrium point and we return to a negative imbalance The same process happens when we get yearly seasonal temperature cycles and also on the approximately 11 year solar energy cycles which change the energy in amounts At all times the amount of energy being transported out of the Earth system is calculated by the Stefan Boltzmann Law SBL based ONLY on the temperature of the Earth system be it at the ground or at the TOA The SBL which says that the energy transported from an object is proportional to the temperature raised to the 4th power ie hotter air rises faster convection or hotter objects radiate more energy per unit time radiation transport is forever trying to reestablish the earth to its equilibrium energy in equals energy out conditions by either warming or cooling it and it is perfectly successful exactly twice each and every day This contradicts the conclusions of the Global Computer Models GCMs which require a permanent or multi decade disequilibrium or energy imbalance to create the global warming So the question is WHY doesn t the Stefan Boltzman Law feedback also automatically compensate for the greenhouse effect Why doesn t the feedback from the SBL automatically return the air to its equilibrium to solar energy in conditions imposed by the daily solar cycles Why isn t the delay in energy transport by adding GHGs compensated for by the speedup in radiation transport at the speed of light caused by the increase in temperature and the SBL response The SBL has no way of differentiating between a GHG or solar caused warming According to the GCMs we already know that the CO2 caused global warming results in hotter air rising faster convection at ground level which Gavin says is included in the GCMs as a part of the water vapor feedback effect How not to attribute climate change comment 182 12 57 pm see also 126 et seq 208 Why doesn t the hotter air at ground level also cause more energy to be radiated out faster per the SBL to result in the greenhouse caused warming energy to be returned to the TOA where the extra energy will cancel out the CO2 caused imbalance at the TOA ie to return the Earth to its equilibrium conditions which it actually does twice a day The conventional wisdom that greenhouse gases cause global warming is based on the identification of the greenhouse effect GHE in the Svante Arrhenius 1896 paper see Wikipedia On the Influence of Carbonic Acid in the Air Upon the Temperature of the Ground However my simple reading of the paper shows that Arrhenius calculated the warming effect of CO2 energy absorption in academic isolation CO2 absorbs energy without considering the real world effects of the Stefan Boltzmann Law Feedback Also a review of the Global Computer Models GCMs results shows that the amount of global warming calculated varies depending upon the duration of the period modeled eg 1950 1997 1880 2000 1750 2000 or from the bottom of the ice age and bottom of the CO2 level 20 000 years ago until 2000 etc This is to be expected except that the computer model also requires that the temperature imbalance at the TOA be equal to and opposite the warming to maintain conservation of energy SO just what is the temperature at the TOA in the year 2000 It HAS to be a single value not the infinite number of options that can result from the GCMs Again the GCMs are calculating results that are not possible BUT if the SBL Feedback returns the TOA to the equilibrium conditions then we have a single value but then there is no energy imbalance However there also is no global warming due to the GHE Sorry Gavin but I feel that the GCMs are giving such fundamentally incorrect inconsistent results that they can NOT be valid They seem to be missing some of the SBL feedback If you can explain these discrepancies please do Which brings us back to what you previously stated 15 months ago Response You refuse to relax your incorrect assumption that the flux from the surface is the same as the flux from the top of the atmosphere which is equivalent to assuming that there is no GHE at all So you assume the result you wish to prove gavin Comment by John Dodds 30 Oct 2005 8 04 pm click on the time stamp to go to Gavin Schmidt s RealClimate org location To which I now respond Yes Gavin I intuitively assumed constant equilibrium flux but it is not my assumption it is the constant flux equilibrium IMPOSED by the Stefan Boltzmann Law Mother Nature s Laws of Physics and seen on a daily basis The SBL Feedback which is dependant ONLY on the temperature and not the CO2 concentration cancels out the GHE temperature effect basically eliminating it as it occurs No GHE means no GHG CO2 induced warming as you said The ever increasing GHG Forcing Curve Planetary energy imbalance May 2005 IPCC is effectively a flatline Any research based on the increasing GHG forcing and the GCMs is invalid The estimates of the temperature impact of doubling the CO2 levels in the next century are just plain wrong This does not mean that global warming does not exist or that adding CO2 does not cause problems such as ocean acidification The evidence in melting polar ice caps glaciers and measured temperatures etc is too obvious However the increases must come from an external increase in energy in or maybe if the solar increases do not explain

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    the primary form of ATP and NADPH and get their electrons by tearing apart water molecules with the aid of sunlight In any case energy that would have been released to space is instead stored up in the land oceans ice sheets and atmosphere and the oceans and atmosphere are convective fluid systems so the heat is transported here and there and evaporation rates increase and that puts more H2O in the atmosphere and the radiation trapping effect grow stronger and to quantify all that and make future predictions various real time observations are made using satellites etc and very complex mathematical models are developed for oceans ice sheets and the atmosphere Now what climate models don t do is attempt to make numerical projections of future CO2 responses rather they work off given scenarios for CO2 emissions The CO2 emission rate is dependent on things like human behavior as well as the biosphere responses but it has been steadily increasing over the past few decades both the rate and the amount This factor along with N2O and CH4 emissions seems to represent the greatest uncertainty in future predictions with the IPCC projections being on the conservative side Its also a factor that humans can control by switching from fossil fuels to renewable energy sources Some people complain that the models are constantly being tweaked so how can you rely on them but that s how weather models work the weather stations constantly send data out which is incorporated into the models for the latest round of predictions Old ice sheet models are similarly being replaced by more accurate modern versions which incorporate new observations about dynamic ice sheet responses as I understand it Endless technical jargon often serves no other purpose than to confuse an issue and exclude outsiders from the discussion which seems to be the intent of some of the above posts 62 L David Cooke says 18 Jan 2007 at 4 34 PM RE 59 Hey Hank The problem is my word processor link the down and welling together and you get 159 hits http google arm gov search q downwelling clear sky night spell 1 access p output xml no dtd ie UTF 8 client default frontend site default collection proxystylesheet default frontend Dave 63 L David Cooke says 18 Jan 2007 at 4 45 PM RE 60 Hey Hank At the risk of not getting the links to pass the filter here they are with a few editorial notes http www arm gov publications proceedings conf15 extended abs long cn pdf http www arm gov publications proceedings conf16 extended abs long cn2 pdf Pay particular attention to page 3 and the recent SW and LW graphs http www arm gov publications proceedings conf15 extended abs nordeen ml pdf http www arm gov science rp presentations 20061004 breakout atmos surface long FlxAnl update 20061003 pdf http www arm gov publications tech reports arm tr 004 1 pdf http www arm gov publications proceedings conf12 extended abs tobin dc pdf This was part of the caliabration resolution work that happened after the noted issue http www arm gov publications proceedings conf11 extended abs charlock tp pdf This is the reason that down welling measurements could be questioned as unknown aerosols can offset the predicted values With an unknown reason for night time expected value being as much as 30 W m 2 lower then projected raises questions regarding the current equipments ability to make these measures These two issues appear to complicate the ability to confirm clear sky nigth radiant measurements http www arm gov publications proceedings conf16 extended poster cook dr2 pdf The issue examined here is not unique depending on the size or design of the detection cavity radiative rate of change can lead to inaccuracies when the detector is operating at the edge of the temperature or bandwidth capabilities of the detector array http www arm gov publications proceedings conf04 extended abs ellingson2 rg pdf The recommendation here appears to suggest to not rely on ARM data until Lidar are installed at the detection sites The AERI Homepage referenced in this paper is found here http cimss ssec wisc edu aeri data https google arm gov search q cache PMWDT8CWO2UJ www arm gov publications tech reports handbooks irt handbook doc night clear sky downwelling access a output xml no dtd ie UTF 8 client default frontend site default collection proxystylesheet default frontend oe UTF 8 Even with the latest equipment there appears to remain issues as it appears the frequency band and the temperature range necessary exceed the capability of the equipment See Specifications These were in the long list with only a few links requiring you to register hopefully these will help Pay particular attention to the date stamps as the more recent indicate that the issues remain and the planned means to deal with them Hopefully I have not missrepresneted anything and Good Luck Dave Cooke 64 L David Cooke says 18 Jan 2007 at 5 07 PM RE 61 Hey Ike The point is your night time radiation of GHG does not appear to be detectable by the current radiative detector systems If you have a reliable source that demonstrates this over time on a daily basis and can docuement the clear sky nightly radiative down welling curves it would be very welcome Please keep in mind that we need a minimum of hourly discrete full spectrum measures with a detector that is stable within 3db across the desired badwidth and a range of 175K to 350K over the local 12 hour period related to the night side of the planet Thanks Dave Cooke 65 Hank Roberts says 18 Jan 2007 at 7 44 PM Please keep in mind that we need a minimum of What s your basis for that Who says we need a minimum of again I can t find your source on the site you point us to Is that your requirement or one from the research Clear sky longwave radiative transfer appears to be largely a solved problem the uncertainty is better than 2 W m 2 Turner et al 2003b we expect that model calculations will yield accurate cooling rate profiles in the spectral interval from 4 to 20 µm Why do you say that s an impossible level of accuracy to achieve You still aren t giving specific sources just pointing to large papers about many instruments which of course take work to put together into a monitoring system 66 L David Cooke says 18 Jan 2007 at 8 43 PM RE 65 Hey Hank Let s start with your first question A description of the curve of radiant decay is a graphic that is easy to over lay for comparitive purposes To be have a high resolution and meet standard deviation or statistical confidence levels the desire would be to collect 30 samples nightly The collection of 1 per hour meets the requirement for describing the mean statistically and because you have solar influences on the upper atmosphere when the ground is in darkness the 10 hours of samples in darkness meet the min requirement best as long as you are measuring winter clear sky night time values near the Vernal or Autmnal Equinox So yes sample rates of 1 per hour is my minimum requirement to meet a minimum level of statistical confidence regarding the description of the mean of a known environment population Note If you read the papers I have provided you will find that ARM makes measurements at 15 min where Spectra AERI the sample rate is 30 min Both meet the min required sample rate the ARM sample rate meets the minimum desired As to your second question you have to read these papers to see the discussion regarding the error and the calculated versus measured deviations Virtually every reference that I have annotated as such there is a description of a question of quality of the data support my conclusion The specific data contained within these papers will point to the limitations of the detectors in regards to the frequency range absolute temperature range and measurement conditions Do you have sources that deny the issues raised in these papers where I have noted specifics Do you have sources that have sufficient accuracy and sample rate required to define the full spectrum downwelling energy for a clear sky night time measure Your reliance on a 2003 paper when there is clearly more recent papers that question the monitoring systems causes me concern Your motives appear to be suspect do you wish to clarify your point Dave Cooke 67 Hank Roberts says 18 Jan 2007 at 10 01 PM I m not arguing with you about this I m showing where I got that direct quote following your search You re quarreling with their cite not mine 68 L David Cooke says 18 Jan 2007 at 10 11 PM RE 67 Hey Hank Funny you appear to purposefully ignore data that is contrary to your position or has been superceded On that stand point I guess there is no reason for further conversation Good Luck to you in your endevors Dave Cooke 69 Hank Roberts says 19 Jan 2007 at 12 21 AM I don t have a position and don t understand what you re arguing with I followed your pointers read the 2004 summary that said Clear sky longwave radiative transfer appears to be largely a solved problem the uncertainty in the calculated longwave flux at the surface is better than 2 W m 2 that s not the new stuff that s the foundation work Do you disagree with the report there That s the first part of the program done on a few sites with the first set of instruments That was the beginning work They got that they say down to a level of accuracy you don t believe I can t say why they claim one thing and you claim another but I am pointing out that you re talking about their more recent work with different instruments in more locations and that of course they will be reporting less accuracy for a while in new locations with new instruments I don t see an argument here Look they reported getting that high accuracy level and cited a 2003 paper That s not the same instrument that you re looking at for 2005 or 2006 it s the first stage work They got to that level then said their next step is rolling out a greater variety of instruments in mobile labs and going to many more sites So with new equipment in new locations they re reporting more variability That s what you d expect from the new mobile labs and new sites what s to argue about there New instruments and new locations are going to give more variable data Publishing the problems is how progress is made Did you read the reports done tracing the Space Shuttle launch plume a few weeks ago at Head in a Cloud here http atoc colorado edu headinacloud where he talks about PUMA a field campaign for making measurements of the chemistry microphysics of the space shuttle plume from aboard the NASA WB 57 That s not final publication that s a scientist blogging his daily work including the uncertainties about the data collection flight This is exciting for an amateur to watch It s not something that proves the science is wrong eh Don t you think these folks are doing something wonderful and right out in public We can cheer them on because the facts that emerge are what s real We re the audience we need to be an inviting one if they re going to talk to us Same for the folks whose work you re pointing us to if they re going to want to discuss their work we need to understand it enough to talk about it So one accuracy level in 2003 at the first stage and later in 2005 6 a variety of different accuracy reports from the second stage It s not that either is wrong it s a question of what were they doing where with what tools So let s charm them into talking to us Why not And that s really far too much from me It s not about me Back to listening and reading 70 Ike Solem says 19 Jan 2007 at 1 06 AM So for those who want to enter the highly technical world of atmospheric radiation calculations the best place I ve found to start is with Spencer Weart s excellent website based on his book The Discovery of Global Warming and having read a lot of introductory books on global warming that one seems to be the best if you want to introduce someone to the topic buy them that book The supporting website has this essay on Basic Radiation Calculations in the Atmosphere As far as measuring the downwelling radiative flux RE 64 you d have to measure it over the whole planet wouldn t you Recall that the reason that Charles Keeling set up his CO2 measurement station in the middle of the Pacific was to avoid local fluctuations in CO2 concentration Then you d have to worry about separating out the CO2 signal from the water vapor signal from other signals CH4 is there a gas flare nearby or a swamp An old leaky fridge putting out CFC s N2O generation Aerosol content Of course you can tell that it s colder at night in the desert then by the coast because there s little water vapor in desert regions so the surface cools off much faster What if a cloud passes overhead It suddenly gets warmer but what about the atmospheric column above the cloud Even if you got simultaneous data from all over the planet at high resolution how would you know what was due to CO2 You re not in a lab you re out in a field on the ocean on a glacier and so on So what do you do The first thing to do is to take the temperature of the atmosphere and monitor it over time that s what the radiosonde ballon network attempted to do followed by the microwave sounding units on satellites which at first appeared to show that the atmosphere was not warming at the rate predicted by the climate models the radiative convective models of the atmosphere terribly complicated beasties that they are That whole topic has been put to rest and the details of the issue are explained with the usual clarity by realclimate Et Tu LT Beyond this it is possible to sort out different radiative signatures using satellites see The Radiative Signaure of Upper Tropospheric Moistening Science Soden et al 2005 So the claim in 64 radiative detection systems do not exist is simply untrue Given a clear theoretical reason why the atmospheric temperature would increase plus an actual measurement of that temperature increase it seems rather obvious that the conclusion is solid You can t rule out invisible aliens from a far away galaxy heating the atmosphere with giant ray guns as part of an elaborate practical joke nor can you rule out deities placing fossils in the earth to test the faith of true believers but come on now As with many other aspects of climate science the observations of atmospheric temperature are now matching the modelled predictions of atmospheric warming The water vapor feedback effect is also matching the modelled predictions of an increase in atmospheric water vapor Those who feel the need for more information on why radiative models are so complicated could start with Richard Feynman s short text QED on the physics of the interaction of light and matter Happily someone recorded those lectures on video at http www vega org uk video subseries 8 so you can read along and watch at the same time Then go back and read the above basic radiation calculations link Repeat this process several times and that s just the front end of the climate models The fact that they are reproducing observations is good evidence of their success these are the most complex computer models ever created as far as I know 71 Jeff Brown says 19 Jan 2007 at 1 06 PM I m a physicist and new to this so pls bear w me I understand that due to computational considerations it isn t possible to generate error statistics for climate predictions in the usual manner e g Monte Carlo simulations or what have you Can anyone point me to some references that deal w these questions how ARE error stats derived and how are they rigorously shown to be equivalent to the usual suspects Thanks 72 Ike Solem says 19 Jan 2007 at 2 37 PM RE 71 Jeff I m not sure what the usual manner is for computing errors in models though there are many not being a modeller but someone who has used models QM classical mixed models and protein structure prediction models it seems that the issue is indeed addressed in some detail in climate modelling studies hope these two references help http www image ucar edu tebaldi talks eap talk pdf Interpolating Climate Model Experiments http curry eas gatech edu currydoc Inoue JC19 pdf Intercomparison of Arctic Regional Climate Models 73 John Dodds says 19 Jan 2007 at 3 20 PM James Re 38 57 1 Re Conduction Energy transport is by 3 mechanisms Convection movement of hotter atoms Conduction movement of hotter electrons and radiation movement of photons Heat is a form of energy In the air both conduction and convection are relatively SLOW heat energy movement processes but they do result in energy transport from the ground to space Radiation since it consists of photon at the speed of light followed by absorption then another photon another absorption etc is very fast in going thru the atmosphere to space according to Eli Rabett a few microseconds for each absorption so we are talking a less than seconds for radiation to transfer energy from ground to space so most energy transport is by radiation Conduction exists in the air because electrons get carried from the ground to the tops of clouds are also created in the air which is why we have charged clouds which result in lightning but we can ignore it since it is small 2 Re Stefan Boltzmann Yes the SBL applies to black bodies where the emissivity constant e 1 but for non black bodies the constant just gets adjusted For the earth it is 0 95 per a lecture on global warming from Columbia University So the principle still applies The energy flux watts m2 IS calculated by the SBL If you know the peak temperature of the radiating energy spectrum then you can calculate the outgoing energy flux If you know the flux you can calculate the temperature Hotter bodies radiate more look at the sun When the GHE for added CO2 raises the ground level temperature then the ground air will radiate MORE back up than what was being radiated pre GHG addition IF the GHE lowers the TOA temperature then the Earth at the TOA will radiate LESS energy both up to space and down If we started pre CO2 at equilibrium conditions then there will be a negative energy imbalance at the TOA meaning that the Earth system will absorb more solar energy than it radiates in addition to the GHG part that is recycled We will warm up 3 Next your simple GW model it is fine up to the last sentence Eventually it increases enough until a new equilibrium is formed Equilibrium for the earth is defined as Energy in equals energy out in the case of our GW computer models energy in is ONLY what comes from the sun If you do not change the energy in then changing the energy out by CO2 absorption can NOT create a NEW equilibrium What has been created in the computer models is a non equilibrium condition where the CO2 absorptions delay or slowdown the rate of transmission of energy to space The longer transit time results in higher ground temps global warming and lower TOA temps to conserve energy See Hansen et al 2005 for these results 4 In your planet A B example The fallacy is in the B will cool faster statement IF the temperature is the same then the planets will transport energy out at the same rate because the only thing that impacts the transport rate is the temperature per the SBL A conceptual analogy if 100gpm of water is pushed thru a 10 ft long pipe and you add a recycle loop that takes 1 gpm from near the outlet and runs it back to near the inlet the water will still flow in and out at100gpm because that is what you are adding at the front end just the friction resistance has changed it takes more power to push the water thru It WILL take a few extra seconds for the water to transition thru the extra recycle loop but AT EQUILIBRIUM the 100gpm will flow thru because we did not change the input This analogy will fail if you try to model the real environment 5 My QUESTION for the experts is can the atmosphere stay in this non equilibrium situation in 2 3 above for 20 30 years per the GCMs or 20 000 if the CO2 keeps increasing as it has since the CO2 low at the bottom of the ice age 6 The GCMs say YES Even with the TOA temp being lower than equilibrium they say that the excess energy that accumulates goes into the ocean and the TOA temp remains unchanged at below equilibrium for years I assume until the CO2 is removed to the ocean So why don t the daily changes in solar energy flow just eliminate the imbalance return to equilibrium 7 The SBL Feedback theory says NO Equilibrium is restored every day It postulates that because the very real GHE raises the ground temp then the raised temp results in more pump power or SBL Feedback to push the energy back out MORE energy being radiated convected conducted back up to the TOA where it came from This larger pumping will push up enough energy to return to equilibrium and accommodate the extra energy that is returned to the ground by the added CO2 The question is will this return the air to equilibrium In parallel the SBL feedback is the same mechanism that returns the earth back to its solar equilibrium on a daily basis ie hotter air rises and radiates faster as the temperature warms every morning The SBL can NOT differentiate between GHG or solar caused temperature increases It is postulated that the SBL effects to return to equilibrium are not properly included in the GCM The conclusion is that GHG warming is negated by the SBL feedback CO2 can increase without changing the temperature see 112 118 126 148 in the section on Al Gore s movie distribution to schools OK GCM experts a comment please 74 Hank Roberts says 19 Jan 2007 at 5 35 PM This may help http climate gsfc nasa gov cahalan Radiation particularly http climate gsfc nasa gov cahalan Radiation RadiativeBalance html John consider why the heat at the core of the Sun doesn t rush straight out into space total Solar energy is determined by the temperature of the Sun s visible surface or photosphere which is about 6000 deg K This in turn is determined by the Sun s core temperature of about 15 000 000 deg K which arises from a balance of inward pressure from gravity and outward pressure from the inner nuclear reactions and the radiative and convective transports of energy from the core to the photosphere 75 Eli Rabett says 20 Jan 2007 at 2 51 AM 70 the way you look at the Earth s radiative signature is put a satellite out at L2 76 Jeff Brown says 20 Jan 2007 at 7 55 AM Re 72 Thank you Now I m going to go one step further and continue to display my ignorance By the usual methods I mean something along the following lines in a particle physics experiment one accumulates a large of events and ultimately derives error bars for whatever you re trying to measure The more events you have the better generally speaking the result the smaller the error bars I gather that it s not feasible to do this w climate models so how does one assign error bars to say sea level rise 10m whatever Anyway I ll check these refs and any other info is greatly appreciated Thanks again 77 Neal J King says 20 Jan 2007 at 10 38 AM 73 John Dodds No the SBL does not apply with an adjusted constant to frequency dependent emissivity If you have a gray body with non frequency dependent emissivity that constant emissivity can be multiplied by the signma T 4 to give SBL But it just doesn t work if the emissivity is not constant as a function of frequency Don t believe me Just go straight to the Planck radiation law and try to integrate it over frequency If there is a non constant emissivity factor you can t do the integral so you can t get to SBL End of story The fact that hotter bodies give off more radiation doesn t mean they satisfy the SBL which is a specific dependence 78 Ike Solem says 20 Jan 2007 at 2 57 PM 76 That gets to the heart of the problem because in climate science there is only one experimental event the ongoing evolution of the land sea ice atmosphere system with no controls or ability to repeat the experiment Thus all experiments must be done in silico imagine if in your particle physics experiments you just had one chance to collect data from one single event you d want to collect as much data as possible of course The chief problem with climate models as with other models and experiments is distinguishing between systematic errors and random errors say you had a tiny piece of metal in your cloud chamber that d create the systematic skewing of results even though the random variance might be very low after hundreds of observed events That 2nd reference seems to use multiple independent models to test for systematic errors in the climate models random variance is apparently tested by running the same model over and over This is why we should have far better data collection systems for monitoring the Earth system more satellites and more ocean sensors bottom moored ones deployed on a global basis to measure subsurface ocean temps and currents and more in situ measurements of ice sheet dynamics in the Antarctic and Greenland as well as measurements of the permafrost behavior it d be a better use of resources than another race to the Moon The only real way to test the models after all is to compare their predictions with actual data on an ongoing basis 79 John Dodds says 22 Jan 2007 at 12 00 PM Re 74 Hank Your quote about the sun contains the key point There is a BALANCE of inward pressure and outward nuclear radiations This is the key for CO2 caused global warming also Nature physics requires a balance energy in equals energy out The equilibrium exists UNLESS you are adding or subtracting energy and adding CO2 does NOT add energy to the earth system The SBL forces a balance in the atmosphere and at all points within the atmosphere IF it gets warmer the SBL radiates more energy out to return to the balance if it gets cooler the SBL radiates less out to return to the balance The SBL is mother natures equilibrium enforcer The Earth on an annual average is at this balance point It passes thru this point twice a day as the solar energy in increases and decreases The GCM computer programs require that the the ground level air be warmer than the equilibrium AND the TOA air be cooler per Hansen THIS IS NOT a balance Even Hansen says that the earth is at an energy imbalance that lasts for years The GCMs are wrong Apparently the GCMs do NOT account for the return of the CO2 absorbed energy to the TOA In fact the SBL hotter air radiates more will force the balance to return the CO2 greenhouse effect warming to the TOA and return the atmosphere to equilibrium balance ie NO NET CO2 caused warming You only get warming if you increase the energy in because the SBL will return you to a balance with the energy in Response John your many comments dogmatic statements about what is or is not in GCMs continue to amuse I appreciate your enthusiasm but rather than make loud declamations why not just check it out There are mutliple GCM codes available for download GISS NCAR EdGCM etc so try looking at them and searching through to find places where SB is used and you ll find it in all of them Long wave radiation is indeed the main balancer against warming effects as has been known and used in all models of the climate even energy balance models for decades already No more nonsense please gavin 80 English says 22 Jan 2007 at 5 37 PM re 79 Sorry to drag this out but I THINK Mr Dodds has made two main points One is that dawn temperatures should be largely unaffected by CO2 as there should be enough time at night for any extra heat to go away There would still be an increase in mean temperature but this is not the whole story at least not for Mr Dodds Can anyone say if this is as measured His other point seems to be that the lower atmosphere IS heating but this extra heat will eventually be passed into the upper atmosphere by conduction and radiation That is if we stopped putting any more CO2 into the atmosphere the mean temperature would eventually fall perhaps slightly after some indeterminate time There would be some overshoot in the lower atmosphere temperature for a step change in CO2 concentration Does anyone know if the models agree with this statement 81 Dan Hughes says 22 Jan 2007 at 6 44 PM re 70 these are the most complex computer models ever created as far as I know I m certain that AOLGCMs are not the most complex computer models ever created How wold you like to start comparing the complexity of computer models of inherently complex physical phenomena and processes that occur in complex physical geometries Close to 100 thousand lines of code is my estimate of the entry level computer model for such applications Truly complex codes consist of a few million lines of code The AOLGCM codes will fall closer to the former estimate than to the latter 82 Bruce Hall says 22 Jan 2007 at 7 25 PM Those darn Chinese are trying to use crude modeling to say that the next 20 years brings cooling instead of warming and that CO2 increases will not be that relevant Multi scale analysis of global temperature changes and trend of a drop in temperature in the next 20 years http www springerlink com content g28u12g2617j5021 fulltext pdf Obviously a Communist plot Response No just rubbish gavin 83 John Dodds says 22 Jan 2007 at 8 33 PM Gavin Thanks for acknowledging I keep asking because you know better what is in the GCM would I ever find that there are 365 0 days in a model year I do not want to become an expert AND philosophically IF my view is to prevail then I have to convince the experts ie you that the GCM is wrong It does me no good to argue about parameter values like Temperature hockey sticks that Monkton Junkscience and most of the other denyers do because I can t win that argument I HAVE to show that the model is wrong or inconsistent or missing something OR accept that it works but a ray of hope for you you readers have guided me thru the entire process of the model from WV feedback to the actual absorption energy return to the air per Eli process I am NEAR THE END in that I am now challenging if Arrhenius the GCMs included the SB process to return to equibrium of not My conclusion is STILL that something is wrong You have NOT refuted my points just ignored them Why can t you just respond to the physics itself I do not understand why the energy imbalance ground warmer TOA cooler would not be equalized by the SB forces After all the SB forces MUST change and be larger because the ground temp is warmer It seems to me that the SB forces to equalize would have to be faster than the CO2 absorbtions because they act on all the air not just the GHGs and they act on daily temperature changes that are much larger than GHGs AND we still return to equilibrium The SB forces especially what I refer to as SB Feedback is automatic to return the system to equilibrium The only reasons I can see to explain them is that somehow they are missing misapplied in the GCMs hence I offer that explanation I will stop asking if the GCMs missed them as you requested BUT please explain the apparent GCM inconsistencies that I identified in 38 Where are they wrong To paraphrase you you are dogmatically insisting that the GCMs are correct which I understand since you have spent so much time on them I identify inconsistencies and you ignore them you do NOT refute them at least way back when when you explained I could move on As it is I have come back to my discussion points from 15 months ago where you said I assumed equilibrium you said that was wrong but not WHY I did assume then BUT now I see that the SB forces should reestablish it see 38 so WHY is it wrong Quite frankly the idea that the inequilibrium energy imbalance could last for many or 20 000 years or as long as the CO2 is increasing just seems impossible After all we go thru equilibrium every day The amount of energy transferred by GHGs is downright trival compared to what flows thru the earth at all times The equilibrium concept must be dominant the documentation for the research publish papers even identifies it as a requirement Hank s sources identify equilibrium as a requirement for the sun earth energy flows and balances So how can the GCM not allow equlibrium for the entire run length OR try this analogy I know analogies always seem to fail eventually but at least this demonstraes why I think we return to equilibrium Think of the energy transport as a frictionless pipe carrying water The energy water in from the sun is 100gpm at equilibrium the energy water at the outlet is 100gpm If I add a GHG recycle bypass line that takes 2 GPM of water energy from near the outlet recycles it to near the inlet then I have simulated the atmosphere with the potential to double or change CO2 igmore the actual numbers use the concept If I suddenly open a valve to allow water to go into the recycle line then it immediately creates the GCM conditions ie more water at the inlet less water at the outlet TOA during the NON equilibrium

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  • The Physics of Climate Modelling « RealClimate
    of a component eg nuclear power the sun methane clathrates etc is defined as adding external energy Entropy says that CO2 in the air can NOT warm itself up by staying as CO2 in AIR unless it gets energy from somewhere The GCMs agree the ground based air is warmed by taking energy from near the TOA see Hansen et al 2005 figure 2e 110 Margo says 26 Jan 2007 at 1 40 PM Gavin I have a whole bunch of question but I d like to ask them one at a time until comments are closed In your article you say The physics in climate models can be divided into three categories The first includes fundamental principles such as the conservation of energy momentum and mass and processes such as those of orbital mechanics that can be calculated from fundamental principles The second includes physics that is well known in theory but that in practice must be approximated due to discretization of continuous equations Examples include the transfer of radiation through the atmosphere and the Navier Stokes equations of fluid motion The third category contains empirically known physics such as formulas for evaporation as a function of wind speed and humidity I assume GCM s don t solve conservation of momentum from fundamental principles since taken literally that requires solving Navier Stokes equations from fundamental principles I also know if you actually do model the NS equations the reason you approximate these is not remotely due to discretization of the continuous equations My questions right now is How is conservation of momentum modeled in a GCM I don t mean how do you discretize the continuous equations I mean what PDEs do you start from assuming you do Do you parameterize things like boundary layer If so how A reference would be fine But I d like something more specific than what I found this NASA page http www giss nasa gov tools modelE modelE html that said nothing more than the solution of the momentum equations is done within the DYNAM which is rather vague The turbulence model tells me you use a Turbulent Kinetic Energy equations TKE Thanks Response What goes into the model at an algorithmic level is described in the published literature i e Schmidt et al 2006 and references therein You main question is not very well posed though Conservation of momentum is ensured by simply making sure that any process that affects the velocities does so in a way that momentum doesn t change this is fundamental A perfect solution of the NS equations would do that of course but so can all imperfect solutions it s just something you can take care of in the formulation Conservation of energy is the same any energy change in one reservoir grid box must be balanced by an equivalent energy change in another reservoir grid box This too is fundamental and much more so than the NS equations I also don t understand your point about how we solve the NS equations At the large synoptic scale the equations can be discretised and stepped forward in time with only minor adjustments to deal with unresolved variability Boundary layer processess are more parameterised but in our model expand out the Reynolds stresses out to thrid order terms but again you need to read the published literature cited above for the gory details gavin 111 Margo says 26 Jan 2007 at 3 23 PM Gavin I can see we have different ideas about the exact meaning of solving conservation of momentum from fundamental principles If someone replaced the momentum equations in a GCM with Stokes Equations which do conserve momentum would you say they modeled conservation of momentum from fundamental principles I d say No But if you d say yes then I ll at least agree that by your definition of fundamental principles the GCM would be solving conservation of momentum from fundamental principles Of course the results would be pathologically wrong Anyway thanks for the paper So far I m reading under d Dynamics The runs here use a second order scheme for the momentum equations This is immediately followed by information describing what you do to track the motion of passive scalars like heat and humidity I m not actually seeing much specificity about how momentum transport is modeled over all Presumably I can look up the papers in the references and eventually find more since the text tells me much of the dynamics is described in an earlier paper Which as we all know not repeating what was already said in an earlier paper is common practice So thanks Response I m not sure I follow you at all Conservation of momentum is a fundamental principle as is conservation of energy Exact solutions of NS satisfy those principles but so must everything else including the discretised versions and the boundary layer scheme gavin 112 Barton Paul Levenson says 26 Jan 2007 at 4 08 PM It is my contention that earth s natural feedback system ie the Stefan Boltzmann law requires that when the CO2 absorbs a photon delays its transport resulting in longer residence time in the air and hence warming then this warming causes the extra energy to be transported out by increased convecton conduction and radiation per the SB Law The SB law says nothing whatsoever about convection or conduction It deals solely with radiation such that the atmosphere will return to equilibrium almost as soon as the extra CO2 absorbtion warms it The greenhouse warming effect will not accumulate or you do not get an ever increasing GHG Forcing curve The earth is always at or near equilibrium which can only be changed by adding more energy and adding CO2 doesn t add energy If you re saying the atmosphere doesn t permanently store a given bit of energy you re right but that has no effect on the temperature of the atmosphere or the ground which do rise when you have more CO2 in the air Equilibrium can be at any temperature And the specific equilibrium arrived it will be a function at least partially of the amount of greenhouse gases in the atmosphere 113 Hank Roberts says 26 Jan 2007 at 4 46 PM There s an extra dot at the end of the Radmath link above this works http www aip org history climate Radmath htm John When I read the AIP page linked above it makes sense to me I can read the papers linked at an amateur level and find that the basic radiation physics seems quite widely agreed on It s basic not just for Earth but for the Sun as well You should put your argument on your web page where people can look at your math maybe It s just scattered here can t follow it From the Radmath page linked above The Earth must radiate back into space as much total energy as it receives to stay in equilibrium Adding gas to the atmosphere moves the site of this emission to higher levels which are colder Cold things radiate less than warm ones so the system must warm up until it can radiate enough For more follow the link to the Simple Models essay Callendar assembled measurements made in the 1930s which showed that at the low pressures that prevailed in the upper atmosphere the amount of absorption varied in complex patterns through the infrared spectrum Solid methods for dealing with radiative transfer through a gas were not worked out until the 1940s The great astrophysicist Subrahmanyan Chandrasekhar and others concerned with the way energy moved through the interiors and atmospheres of stars forged a panoply of exquisitely sophisticated equations and techniques The problem was so subtle that Chandrasekhar regarded his monumental work as a mere starting point It was too subtle and complex for meteorologists end quote And that seems to be the problem 114 Margo says 26 Jan 2007 at 5 18 PM Gavin I agree conservation of momentum and energy are fundamental principles I think we are differing on a matter of semantics I guess this is going to be long but let me explain how I parse the term solving conservation of momentum form fundamental principles Let me start with an example Suppose we examine steady fully developed flow or a viscous flow in a horizontal pipe We can write down the NS equations We can then simplify knocking out convective terms because the flow is steady and fully developed Then we can solve the resulting equation in closed form We get a poiseuille flow solution In this case by my definition one has solved conservation of momentum from fundamental principles This is because both of the following apply a momentum is conserved in the solution and b we used fundamental principles to describe conservation of momentum Now supposed flow is turbulent and though fully developed and steady on average We still know the Navier Stokes equations but because the flow is inherently unsteady we can no longer knock out the convective terms to obtain a solution Of course we can try schemes to develop models to estimate the effect of the convective terms But we know any model we develop does not describe transport of momentum from fundamentals The turbulence model is an approximation Depending on the model we concocted we may be able to solve the new set of approximate equations in closed form Or we many need to use computational methods But either way once we introduce the turbulence model while our system of equations do conserving momentum which is a fundamental principle our system of equations is no longer based on fundamental principles govering transport of momentum Consequently the way I see it if you stuff these into a code the code and the resulting solutions are not fundamental principles governing transport of momentum Note the non fundamental issue has nothing to do with discretization error differencing schemes or any details involved in stuffing this into a code I m actually fine with that So to say it a different way to my way of thinking conserving momentum alone is a necessary but not sufficient condition to permit us to claim a code solves conservation of momentum from fundamental principles Now I know you may believe my definition is too strict But if we permit the laxer definition for the meaning then momentum from first principles type models could give widely inaccurate predictions for pressure drop vs bulk velocity in pipe flow and that s a bulk feature Needless to say if I extended this example to flow with heat transfer and used the lax definition for energy transport based on fundamental principles I make these sorts of fundamental models give atrociously bad predictions for the temperature gradient as a function of heat addition at the pipe walls And of course pipe flow is much easier than climate modeling Of course none of this implies that all models are bad or that climate models are bad I m fine with models if they are used appropriately It just means that I found your paragraph confusing Mostly reading the paragrpah I wanted to know what really happens in the code so thanks for the reference Response This all appears to be due to a misreading of what I wrote go back to the original paragraph The first includes fundamental principles such as the conservation of energy momentum and mass so far so good right All of these are fundemantal principles and processes such as those of orbital mechanics that can be calculated from fundamental principles it is the processes that can be calculated from fundemental principles The statement that you appear confused about appears nowhere in anything I ve written gavin 115 Margo says 26 Jan 2007 at 6 13 PM Gavin it is the processes that can be calculated from fundemental principles The process of conservation of momentum is not calculated from fundamental principles describing transport of momentum in a GCM It s just not Response Conservation of momentum is not a process Convection is a process and must conserve momentum Drag from unresolved gravity waves in the stratosphere is a process and must conserve momentum I just don t get what point you are trying to make gavin 116 Hank Roberts says 26 Jan 2007 at 7 50 PM Hansen et al 2005 figure 2e Where 117 William Astley says 26 Jan 2007 at 10 49 PM In reply to Response The 8 2kyr event has nothing to do with solar and everything to do with huge lake discharges The chances of it happening today are zero Please keep it real The above comment is meant to be taken literally There is no possibility that a pulse of water from the Glacial Lake Agassiz could today stop the THC There is no Lake Agassiz today The above comment does not question or address the data or analysis that supports the hypothesis that there will be a sudden increase in cloud cover when the current high solar activity ends If there is an increase in cloud cover all agree the planet will cool The assertion that there will be an increase in planetary cloud cover and cooling would be correct even if the 8200BP cooling event was not caused by solar or geomagnetic field changes there was a drop in the magnitude of the earth s magnetic field just before the 8200BP cooling event Two comments concerning the hypothesis that a pulse of water from Lake Agassiz stopped the THC and that the THC stoppage caused the 8200 BP cooling event 1 Concerning mechanism I thought the THC currently was reduced by 30 No cooling todate Is the THC cooling or warming mechanism non linear 2 Timing of the melt water pulse in relationship to the 8200BP cooling event See figure 4 in the attached paper The largest early Holocene melt water pulse 1B occurred 2 thousand years before the 8 200 cooling event Is there cooling after each melt water pulse Why does the cooling occur after the smallest pulse http people ku edu lgonzlez NewFiles Publications Dennistonetal00 pdf There is an anomalous drop in the earth s magnetic field recorded in volcanic flows immediately prior to the 8200BP temperature drop 118 Margo says 26 Jan 2007 at 11 44 PM Gavin Orbital mechanics is also not a process Neither are fluid mechanics solid mechanics continuum mechanics nor just plain mechanics Yet you wrote The physics in climate models can be divided into three categories The first includes fundamental principles such as the conservation of energy momentum and mass and processes such as those of orbital mechanics that can be calculated from fundamental principles If you are saying that GCMs do not model conservation of energy momentum or mass from fundamental principles I agree If you say conservation of mass momentum and energy are not processes I agree with that too I would go further and note that GCM s don t model many of the dominant processes involved in transport of mass momentum or energy If you are saying your original two sentences convey the impression that GCMs do not calculate conservation of mass momentum or energy from mathematical models derived from fundamental principles because those three are principles and not processes and that the only things you are claiming are calculated from fundamental principles are the physical processes of orbital mechanics well I guess I m not going to worry about that claim After all I think we ve resolve this GCM s do not describe the all the physical processes involved in conservation of momentum in any way that could be characterized as solving conservation of momentum using mathematical representations that are derived from fundamental principals Or are you still disagreeing on that If you need to understand the process or processes that are not modeled using mathematical models based on fundamental principles they are Momentum diffusion by small scale turbulent motions and momentum diffusion by any sub grid scale structures Diffusion by these two processes leading order in at least some portions of the flow field and they are modeled in GCMs The reasons why GCMs don t capture these have nothing to do with discretization If you don t understand this I m not going to worry about it further Response If your point is that not everything is included in GCMs then just say so and you will have no argument from me And if you want to point out that sub grid scale flows are not well dealt with then again no argument But semantic parsings of distortions of statements I didn t make is pointless Processes in the GCM conserve momentum energy and mass Are all processes included No gavin 119 Jim Cross says 27 Jan 2007 at 10 29 AM Re 117 William what s your source for a 8000y solar cycle Your link only shows that abrupt cooling took place 8200 years ago Even if solar cycles have more influence than is usually appreciated in this forum it doesn t mean every cooling or warming is the result of a solar cycle influence whether it be from GCR or some other mechanism I seen a lot on 100Ky year cycle from Muller and more recently from this http arxiv org abs astro ph 0701117 I ve also seen a lot of discussion of 1500y cycles in this forum and other places But nothing much on 8000y 120 William Astley says 27 Jan 2007 at 12 32 PM In reply to Jim Cross comment 119 to my comment 106 1 In my comment 106 I included a link to a paper that notes cloud cover has decreased by 5 from the time of 1994 1995 to 2001 2002 The paper I linked to notes a reduction in cloud cover of 5 translates into an increase in solar forcing of 7 5 W

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  • 1981 376 115 147 1982 300 109 109 1983 094 055 149 1984 067 082 053 1985 212 200 057 1986 276 271 140 1987 412 292 131 1988 447 365 247 1989 429 400 324 1990 508 435 318 1991 506 406 355 1992 518 459 355 1993 647 447 341 1994 688 406 471 1995 705 412 327 1996 859 276 218 1997 865 317 385 1998 918

    Original URL path: http://www.realclimate.org/data/scen_ABC_temp.data (2016-02-13)
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  • 566655915761874 358 809997558594 0 310255415864073 1 85935334349549 0 317346826075239 0 544900315855140 1995 361 749309395743 0 312796461099525 2 06288290997971 0 692096567727344 1 18154607662019 361 642353170634 0 312659366875449 2 01257111657708 0 344017108674099 0 587712615903487 360 309997558594 0 310877572580643 1 86865011021297 0 321484606373610 0 553755122724524 1996 363 531733829912 0 313803172237592 2 09382615362940 0 718711635605841 1 22720685288995 363 376419745672 0 313602129330101 2 03269682774285 0 356393576117355 0 609130839388286 361 809997558594 0 311495595380802 1 87799336076403 0 324050732797045 0 560282611361988 1997 365 341096159120 0 314846341797915 2 12523354593384 0 746063908471651 1 27419390575117 365 127913979132 0 314567650845492 2 05302379602028 0 368948186886108 0 630918313724388 363 309997558594 0 312109511732330 1 88738332756785 0 325066021646812 0 564498245618964 1998 367 177803497507 0 315927264434417 2 15711204912285 0 774176808994387 1 32254805358627 366 897011021891 0 315556514926016 2 07355403398048 0 381685491725271 0 653082919706984 364 809997558594 0 312719348920501 1 89682024420569 0 324551013515639 0 566417386597434 1999 369 042269111955 0 317047280942692 2 18946872985969 0 803074460303624 1 37231135504360 368 683887785118 0 316569319798671 2 09428957432029 0 394610120701667 0 675632694533672 366 309997558594 0 313325134049289 1 90630434542672 0 322525976939424 0 566055293332604 2000 370 934912515072 0 318207779903380 2 22231076080759 0 832781707491490 1 42352714682804 370 488722957970 0 317606678786094 2 11523247006349 0 407726784973447 0 698575834982604 367 809997558594 0 313926894042579 1 91583586715385 0 319010912000589 0 563427123471149 2001 372 856159559591 0 319410199384085 2 25564542221970 0 863324139767865 1 47624008264234 372 307139599890 0 318662712524475 2 12580863241381 0 420946503645420 0 721780614381439 367 809997558594 0 313926894042579 1 91583586715385 0 314785664089403 0 559683435473501 2002 374 806442534183 0 320656028701910 2 28948010355299 0 894728113288061 1 53049617331430 374 134671092954 0 319731264934061 2 13643767557588 0 434178263328887 0 745111071359877 367 809997558594 0 313926894042579 1 91583586715385 0 310616378903124 0 555964622387336 2003 376 786200260726 0 321946810248778 2 32382230510629 0 927020774673527 1 58634282814586 375 971363125543 0 320812548075595 2 14711986395376 0 447423785270989 0 768569183509715 367 809997558594 0 313926894042579 1 91583586715385 0 306502315224517 0 552270518931461 2004 378 795878193039 0 323284141381771 2 35867963968288 0 960230085246688 1 64382889752133 377 817261615051 0 321906777062780 2 15785546327353 0 460684786822862 0 792156943550314 367 809997558594 0 313926894042579 1 91583586715385 0 302442741653649 0 548600960922892 2005 380 835928517115 0 324669676380800 2 39405983427813 0 994384846001706 1 70300471681317 379 672412709035 0 323014170109429 2 16864474058989 0 473962981681201 0 815876359512174 367 809997558594 0 313926894042579 1 91583586715385 0 298436936477858 0 544955785269558 2006 382 906810252865 0 326105128476016 2 42997073179230 1 02951472333361 1 76392215162468 381 536862786367 0 324134948577318 2 17948796429284 0 487260080128539 0 839729454922155 367 809997558594 0 313926894042579 1 91583586715385 0 294484187543453 0 541334829963052 2007 385 008989357394 0 327592271947426 2 46642029276918 1 06565027554888 1 82663464441051 383 410658458393 0 325269337024758 2 19038540411431 0 500577789272269 0 863718268990343 367 809997558594 0 313926894042579 1 91583586715385 0 290583792129100 0 537737934071430 2008 387 142938829848 0 329132944299308 2 50341659716072 1 10282298018141 1 89119726251679 385 293846570101 0 326417563255893 2 20133733113488 0 513917813282445 0 887844856798588 367 809997558594 0 313926894042579 1 91583586715385 0 286735056820899 0 534164937732062 2009 389 309138817839 0 330729048512077 2 54096784611813 1 14106526213827 1 95766674768421 387 186474201289 0 327579858370739 2 21234401779055 0 527281853628408 0 912111289490735 367 809997558594 0 313926894042579 1 91583586715385 0 282937297389101 0 530615682144521 2010 391 508076725483 0 332382555374358 2 57908236380990 1 18041052270064 2 02610156705858 389 088588667746 0 328756456815972 2 22340573787950 0 540671609314258 0 936519654464560 367 809997558594 0

    Original URL path: http://www.realclimate.org/data/H88_scenarios.dat (2016-02-13)
    Open archived version from archive


  • 686302980571542 1981 0 918436647814552 0 731590110980443 0 728129291664383 1982 0 967954362510602 0 770234204386276 0 763270797689855 1983 1 02646767789690 0 817974065580862 0 807465918071163 1984 1 09573764584272 0 876564185070484 0 862468755157983 1985 1 15331405585417 0 923553397012077 0 905605643571503 1986 1 21137968557051 0 970990224771361 0 948700568727162 1987 1 27044672526189 1 01913311183707 0 992008466018873 1988 1 33053848943276 1 06799609834269 1 03553978616818 1989 1 39167892190912 1 11759357436326 1 07930524723184 1990 1 45389261445801 1 16794028999016 1 12331584335908 1991 1 51720482594896 1 21517851349977 1 16299003160478 1992 1 58164150207173 1 26283915174414 1 20100451923594 1993 1 64722929562524 1 31092826914104 1 23737422981892 1994 1 71399558739295 1 35945203543061 1 27211393471058 1995 1 78196850762008 1 40841672780897 1 30523825481788 1996 1 85117695810878 1 45782873309667 1 33676166233472 1997 1 92165063494745 1 50769454994215 1 36669848245633 1998 1 99342005189114 1 55802079106080 1 39506289507158 1999 2 06651656440994 1 60881418550987 1 42186893643348 2000 2 14097239442328 1 66008158099979 1 44713050080823 2001 2 21682065573804 1 70774027744136 1 44415483510443 2002 2 29409538020907 1 75550250178424 1 44120814426339 2003 2 37283154464132 1 80337016855195 1 43829011386861 2004 2 45306509845305 1 85134520198751 1 43540043320722 2005 2 53483299212042 1 89942953623443 1 43253879522395 2006 2 61817320642413 1 94762511551760 1 42970489647570 2007 2 70312478251957 1 99593389432403 1 42689843708679 2008 2 78972785285249 2 04435783758333 1 42411912070463 2009 2 87802367294287 2 09289892084814 1 42136665445609 2010 2 96805465406042 2 14155913047441 1 41864074890438 2011 3 05986439681603 2 19015261434939 1 41594111800645 2012 3 15349772569395 2 23849397330159 1 41326747907097 2013 3 24900072455073 2 28658585658147 1 41061955271684 2014 3 34642077310754 2 33443088089331 1 40799706283226 2015 3 44580658446359 2 38203163091662 1 40539973653423 2016 3 54720824365924 2 42939065981694 1 40282730412871 2017 3 65067724731862 2 47651048974640 1 40027949907113 2018 3 75626654440246 2 52339361233414 1 39775605792753 2019 3 86403057810315 2 57004248916708 1 39525672033616 2020 3 97402532891523 2 61645955226096 1 39278122896951 2021 4 08630835891573 2 66264720452226 1 39032932949693 2022 4 20093885729035 2 70860782020090 1 38790077054763 2023 4 31797768714251 2 75434374533414

    Original URL path: http://www.realclimate.org/data/H88_scenarios_eff.dat (2016-02-13)
    Open archived version from archive



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